If you have been using any of the new Safari Extensions you might want to peek inside them to see how they work. Fortunately this is really easy because .safariextz files are just xar archives that can be extracted using the Terminal. Here's how you do it.

Start by downloading the Safari extension. It should come in the form of a file with a .safariextz extension. If you wanted to install the extension to use it in Safari you would just double-click it, but don't do that now as the file will disappear from your Downloads folder.

Instead open Terminal, located in the Utilities folder inside the Applications folder. In the window that appears, type the following line and then press return.

cd ~/Downloads/

This should be the path to the folder where the .safariextz file is located. You will need to change this if you have saved the extension somewhere else. For example you might use

cd ~/Desktop/Extensions

or

cd /Users/matt/Documents/safariextensions/

If you are new to using the Terminal, note that starting with ~/ is a shortcut to inside your user folder, and starting with / is for inside your hard drive. The cd command is for changing directory, i.e. 'moving' to a folder.

Next paste in the following line and press return.

 xar -xf 'TheExtensionName.safariextz'

You need to replace TheExtensionName with the filename of the extension. The quotes around the filename are only really important if it contains spaces. If you want to avoid typing in the name, you can just drag the file into the Terminal window from the Finder and it will be entered for you.

After you press return, a new folder will appear with the same name as the extension. This folder contains all the javascript, plist and HTML files that make up the extension. You can then go to the Extension Builder in Safari and click the plus (+) button to add the extension and edit it.

Try this out with some of the extensions I've made. Feel free to use any of my code for your own extensions. If you are feeling nice, leave a link back to http://www.macosxtips.co.uk/extensions.

Every time Apple brings out a new version of OS X, we compile a list of our favourite Terminal commands for enabling hidden features and changing hidden settings (here are the lists for Tiger and Leopard).

For those who are new to Terminal Commands, here's a quick run down of how to use them. Don't worry, it's really easy. Start by opening up Terminal, located in the Utilities folder in the Applications folder. In the window that appears, paste in one of the lines provided below, and then hit return. For the changes to take effect, you need to restart the application concerned. For applications like the Dock or Finder, it is easiest to just type killall Dock or killall Finder into the Terminal to restart them. To reverse the changes, you just need to change the last word of the command and run it again. If the last word is YES, change it to NO, change 1 to 0, and change TRUE to FALSE and vice versa for all.

1. Folder previews in Quick Look

This is my favourite hidden feature in Snow Leopard. When enabled, using Quick Look (hit the space bar) on a folder will show you a preview of the folder's contents inside a translucent folder icon. The previews of the files inside the folder also cycle through so you can see all of them. Just use the following command:

defaults write com.apple.finder QLEnableXRayFolders 1

You will need to restart the Finder, either by typing killall Finder into the Terminal or by Control-Option-clicking on the Finder in the Dock and choosing Relaunch.

2. Globally enable Text Substitutions

You may have realised that the new text substitutions feature in Snow Leopard isn't enabled in all applications by default, most noticeably in Safari. To enable it , you need to right-click on a text box and choose Substitutions then Show Substitutions. To globally enable text substitutions, use the following three commands one at a time. The first one will enable substitutions, while the second will enable dash replacement and the third will enable spell checking.

defaults write -g WebAutomaticTextReplacementEnabled -bool truedefaults write -g WebAutomaticDashSubstitutionEnabled -bool truedefaults write -g WebContinuousSpellCheckingEnabled -bool true

If you decide there are some specific applications where you want to disable these again, you can do it in the normal way. As always you will need to restart each application for the changes to take effect.

3. Bring back AppleScript Studio palette

As of Snow Leopard, AppleScript Studio has be deprecated in favour of AppleScriptObjC. You can still work on AppleScript Studio projects, but you can't create new ones, and the AppleScript Studio palette in Interface Builder is gone. To bring it back, use the following command:

defaults write com.apple.InterfaceBuilder3 IBEnableAppleScriptStudioSupport -bool YES

4. Disable "focus follows mouse" in Terminal

In Leopard there was a Terminal command to make the Terminal's window focus change with mouse movement. If you had previously enabled this, you will find things don't work quite right in Snow Leopard when you use Command-Tab to switch between applications in different spaces. To fix this, you will need to disable the focus follows mouse behaviour using the following command:

defaults write com.apple.Terminal FocusFollowsMouse -string NO

5. Force Dictionary to only use one window

If you aren't a fan of using Command-Control-D to quickly look up definitions, you might use the "Look up in Dictionary" contextual menu item or Services menu item. In Snow Leopard, each word you look up using these methods opens in a new Dictionary window, which gets a bit annoying. To make each word you look up open in the same window, just use the following command:

defaults write com.apple.Dictionary ProhibitNewWindowForRequest -bool TRUE

6. Change the behaviour of the green zoom button in iTunes

With the release of iTunes 9, Apple messed around a bit with the behaviour of the green zoom button in iTunes. Things are back to normal as of iTunes 9.01, but briefly the green button maximised the window instead of switching to the mini-player. If you liked the temporary change, you can bring it back using the following command:

defaults write com.apple.iTunes zoom-to-window -bool YES

Of course, you can always get the alternative behaviour by holding the Option key and clicking in the green button.

7. Debug menu in Address Book

The debug menu has been available in Address Book for some time, but there are some new additions in Snow Leopard. If you don't already have it enabled, the command is:

defaults write com.apple.AddressBook ABShowDebugMenu -bool true

Restart Address Book, and then click Debug in the menu bar to see the new options. You can enable reflections under contacts pictures, get to the "People Picker Panel" and enable a debug panel called "Ye Olde Debug Settings".

8. Autoplay movies in QuickTime X

One of the weird things about the new version of QuickTime is that it has no Preferences. Luckily you can still change things using the Terminal. To make a movie automatically start playing when you open it, use the following command:

defaults write com.apple.QuickTimePlayerX MGPlayMovieOnOpen 1

9. Keep QuickTime in full screen when switching applications

If you are watching a movie in full screen in QuickTime and you use Command-Tab to switch to another application then the movie will automatically exit full screen. To make it stay full screen in the background, use the following command:

defaults write com.apple.QuickTimePlayerX MGFullScreenExitOnAppSwitch 0

10. Disable Rounded corners in QuickTime

If the slightly rounded corners of movies in QuickTime bug you, use the following command to disable them:

defaults write com.apple.QuickTimePlayerX MGCinematicWindowDebugForceNoRoundedCorners 1

11. Always or Never show titlebar and Controller in QuickTime

The following two commands either permanently enable or disable the titlebar and controller that pop up when you mouse over a movie in QuickTime:

defaults write com.apple.QuickTimePlayerX MGUIVisibilityNeverAutoshow 1defaults write com.apple.QuickTimePlayerX MGUIVisibilityNeverAutohide 1

12. Automatically show closed captioning and subtitles on opening

This turns on subtitles and closed captioning automatically when you open a movie that supports them.

defaults write com.apple.QuickTimePlayerX MGEnableCCAndSubtitlesOnOpen 1

13. Make list view stacks work like grid view Stacks

This command slightly changes the behaviour in Stacks in list view. Once enabled, they act more like grid view Stacks, but with a single list of files and icons on the left. The main difference is when "drilling-down" through folders within the Stack.

defaults write com.apple.dock use-new-list-stack -bool YES

You will need to restart the Dock for changes to take effect. The easiest way is to use killall Dock in the Terminal.

14. Enable mouseover highlight in stacks

If you want items in grid view stacks to highlight when you move the mouse over them, use the following command. It's slightly different from the equivalent in Leopard. Also, note that you can get the highlight behaviour in Snow Leopard without using this command by using the arrow keys to select items in a stack, or by clicking and holding on a stack before dragging the mouse up onto the grid.

defaults write com.apple.dock mouse-over-hilite-stack -boolean yes

You will need to restart the Dock for changes to take effect. The easiest way is to use killall Dock in the Terminal.

15. Set a precise screensaver password delay

A useful new feature of Snow Leopard is the ability to set how long your Mac is asleep or how long the screen saver is on before it requires a password to wake up again. You can access this from the Security section of System Preferences. However, you have to choose a time period from a drop-down menu, and you can't enter your own custom time period. To do this, use the following command. The number at the end is the time in seconds. For example 1800 is 30 minutes, which bizarrely isn't an option in the drop-down menu.

defaults -currentHost write com.apple.screensaver askForPasswordDelay -int 1800

You'll find Network Utility in the Utilities folder inside the Applications folder. It comes free with every Mac, and it's great for figuring out what the problem is with a dodgy internet connection.

Everything you can do in Network Utility you can actually do in a Terminal window using unix tools. But why go to all that effort when Apple have created a nice application that lets you do things much more easily.

When you first open up Network Utility you will see nine tabs along the top [Update: eight in Snow Leopard]. Here's a run through of what you can do in each tab.

1. Info

The first tab, Info, unsurprisingly gives you general information about your network. The Network Interface drop-down menu shows all the different ways your Mac can connect to the Network. Typically these are ethernet, wireless and Firewire.

The useful bits of information are the Hardware Address and IP Address. You will only have an IP address if that network interface is connected, otherwise it will say unknown. The Hardware Address, otherwise known as a MAC address, can be used to uniquely identify your computer (even though it is possible to change it).

One useful way to use the MAC address is when setting up your wireless router. You can set most routers to only allow specific MAC addresses to join, meaning other people can't log onto your wireless and connect to the internet.



2. Netstat

Netstat is a tool that is really useful to network administrators for troubleshooting, but pretty useless to the average user. If you choose "Display routing table information" and click Netstat, you will get a list that contains all the computers on the network. For example, I get Matts-Macbook, Matts-iPhone and ChrisG5.

If you choose "Display the state of all current socket connections" and click Netstat you'll see a list of your computer's network connections. For example, the first items on the list will correspond to any web pages you have open. If you type the numbers under "Foreign Address" into Safari, the web page will sometimes appear.



3. AppleTalk

The AppleTalk tab is very similar to the Netstat tab, but specifically for Apple's proprietary protocol called AppleTalk. It was very popular in the early days of the Mac, but now has been pretty much abandoned and is unsupported in Snow Leopard. You can read more about AppleTalk on its Wikipedia page.
[Update: The AppleTalk tab is completely gone in Snow Leopard]

4. Ping

Ping is a tool to check if an internet address is working. When you "ping" an address, you send a small bit of data which it sends back.

You can use this to check if a website is down if it isn't loading in Safari. Alternatively, if you think your internet connection is down, you can try pinging sites that almost never go down like google.com and bbc.co.uk to see if you have a problem on your end.



5. Lookup

Lookup allows you to get information about a web site or IP address. The drop-down menu allows you to choose from a number of different types of information. For example, performing a Name Server lookup on macosxtips.co.uk will tell you that this site is hosted by Dreamhost, and a MX record lookup will tell you that our email is handled by Google.



6. Traceroute

When you enter an address and click Trace, traceroute will show you the route taken by data sent between you and the server. It allows you to see all the servers that your data goes through along the way.

You can use this to troubleshoot connection problems by finding out the point where your data is being blocked.

You can also use it when you are downloading a file and have multiple download mirrors in different locations to choose from. Just type the addresses of the mirrors into traceroute and you can get a good idea of which mirror is fastest.



7. Whois

The Whois database gives you information about internet addresses and who has registered them. The default whois server whois.internic.net works quite well for most addresses, but you might have to type "domain apple.com" for example to get it to work. For .co.uk addresses use "whois.nic.uk" as the whois server. You will get information like the registrant, their address, who they registered with, when their registration was started and and when it expires.



8. Finger

Finger, created in 1971, is one of the earliest forms of status updates that are now done using Facebook and Twitter. It's hardly used anymore, but you can use finger to check if your friends are online, and you can post .plan files to your profile similar to blog posts.

One of the best ways to use finger is to type in your username or the username of another user on your Mac. It will tell you if they/you are currently logged in and how long since they/you last logged in.



9. Port Scan

The final tab in Network Utility, Port Scan, is for scanning which ports are open at a certain address. These Network ports are a sort of virtual version of the ports on the side of your computer, and each port is for a certain type of network traffic. For example, port 80 is used for web pages.

You can use Port Scan to test your own computer by typing in the name of your Mac followed by ".local". You can find this name in the Sharing section of System Preferences.

Things like iTunes sharing, instant messaging, BitTorrent, AFP and SMB sharing all use different ports. If you find that one of these isn't working, it might be because your firewall is blocking the port that it uses. Instead of turning off your firewall, you can just set it to open that port.

Just run Port Scan with the application or sharing turned off and then again with it turn on to see which port appears. You can then set your firewall to open this port and allow network traffic through. Note that the built in firewall that comes with Mac OS X works on a per application basis rather than a port basis, to keep things simpler for the average user.

Spotlight works great most of the time, but occasionally you may need to do a bit of tinkering to get it to work properly. Most of us have probably had a problem where Spotlight won’t find a file you know is there. Here are a few Terminal commands for changing hidden Spotlight settings, performing more complicated searches and updating the index.

Add a file to the Spotlight index
In theory, all files are added to the Spotlight index when they are created. However, every now and again something goes wrong and a stubborn file might refuse to show up. To manually add it to the index, you can use the following command. Start by opening up Terminal (located in Applications/Utilities). Type in mdimport and then hit the space bar. Next, find the file you want to add in the Finder, and drag it onto the Terminal window. Terminal should automatically type in the path to the file for you. Of course, if you know the path you can type it in manually yourself. Finally, hit return and the file should now show up in you Spotlight searches.

Add a folder to the Spotlight index
Adding a folder works in exactly the same way as with a file. However, in Mac OS X 10.4 Tiger and earlier, the command is slightly different if you want the contents of the folder to be indexed too. In that case use mdimport -f instead. You might want to use this to add the System folder with mdimport -f /System as it isn't searchable by default.

Search Spotlight from the Terminal
Considering Spotlight is so quick and easy to access, you will probably only use this if you are already working in the Terminal and want to find a file, or if you want some extra options. To do a search, just type mdfind query where query is what you want to search for. To limit this to a specific folder, instead use mdfind -onlyin ~/Desktop query replacing ~/Desktop with the path to your folder. To run a "live" search which will update the results as users add files, use mdfind -live query. Control-C will stop it updating. To see all the other options, look at the man page by typing man mdfind into Terminal.

Re-index an entire drive
If you are having problems with your Spotlight index, you might want to start over and re-index your hard drive. In the Terminal, type sudo mdutil -E / and hit return. You may have to enter your password. The existing Spotlight index will be deleted, and Spotlight will start creating a new index in the background. You can re-index other hard drives by changing the command to include their name, like sudo mdutil -E /Volumes/OtherHardDrive.

Re-index a specific file format
When Spotlight adds a file to the index, it checks to see if it recognises the file type and then uses an mdimporter plugin to index the contents if it does. Each file format has it's own plugin, and most are located in Macintosh HD/System/Library/Spotlight or Macintosh HD/Library/Spotlight. Double clicking on a plugin will give you the option to re-index all the files associated with it. Alternatively, you can do this from the Terminal with the command mdimport -r. For example, mdimport -r /System/Library/Spotlight/Chat.mdimporter would cause all of your chat files to be re-indexed.

Add a new file format to the Spotlight index
One of the great things about Spotlight is that it will index the contents of many types of files. For example you can search for a word written in a PDF document or the telephone number of one of your contacts. Many third party applications require plugins to make Spotlight index their file's contents, which are available on the Apple Spotlight plugins page.


Make Spotlight index source code
Apple's developer tools come with a source code mdimporter plugin that allows Spotlight to search the contents of your source code. However, if don't want to install the developer tools (it's a big download) then you can just modify the rich text mdimporter plugin to handle the same job. Go to Macintosh HD/System/Library/Spotlight and find the RichText.mdimporter file. Right-click on it and choose "Show Package Contents". Inside the Contents folder, double-click on the info.plist file to open it in TextEdit. Near the top you will see a list that looks like this:

<string>public.rtf</string>
<string>public.html</string>
<string>public.xml</string>
<string>public.plain-text</string>
<string>com.apple.traditional-mac-plain-text</string>
<string>com.apple.rtfd</string>
<string>com.apple.webarchive</string>
<string>org.oasis-open.opendocument.text</string>
<string>org.openxmlformats.wordprocessingml.document</string>

You can add any of the following lines to the end of this list to enable Spotlight to index the contents of the specified format:

<string>public.c-header</string>
<string>public.c-plus-plus-header</string>
<string>public.c-source</string>
<string>public.objective-c-source</string>
<string>public.c-plus-plus-source</string>
<string>public.objective-c-plus-plus-source</string>
<string>com.sun.java-source</string>
<string>public.perl-script</string>
<string>public.python-script</string>
<string>public.csh-script</string>
<string>public.shell-script</string>
<string>public.ruby-script</string>
<string>public.php-script</string>
<string>com.netscape.javascript-source</string>

When you are done, you will want to double-click on RichText.mdimporter to re-index all these file formats.

If you have another file format that is a really just a text file under the hood, you can find out what to add to the info.plist file by running mdimport -n -d1 somefile.ext in the Terminal. The output should contain a "type" that looks something like the items in the list above.

Remove something from the Spotlight index
This is really straightforward, but I thought I'd include it for completeness. Simply go to System Preferences and click on Spotlight. In the Privacy tab, click the plus (+) and choose your file or just drag it from the Finder.

Here is a collection of 10 tips that are slightly more advanced than usual. They are aimed at those who want to become more expert Mac users - and of course those who think they already are experts... In general these tips will help you save time and effort when carrying out day to day tasks and hopefully introduce some concepts and applications you may not have come across before.

1. Download Quicksilver
This is really the most important pro app for Mac OS X. The principle of Quicksilver is simple, but it is amazingly powerful: Hit a hotkey, then start typing what you want to do. You can open an application. Send an email to a certain contact. Pause iTunes. Anything (more or less). But what makes this so incredible is that Quicksilver learns over time so you can get what you want faster and more efficiently with less and less effort. Head here for a more detailed explanation, or if you've got some time to spare, watch this demo video. Download it from the Blacktree site.

2. Get to grips with keyboard shortcuts
This may seem like a really simple tip, but far too often I watch supposedly experienced computer users take forever performing simple tasks like copying and pasting. The fact of the matter is keyboard shortcuts make everything easier, but not only do you have to learn them, you have to get into the habit of using them. There is a hugely extensive list here, but to be honest nothing will save you more time than getting into the habit of using shortcuts for quitting, closing windows, copying and pasting and switching applications.

For the more adventurous, you can create your own keyboard shortcuts in the keyboard and mouse section of System Preferences. And if you want to go even further, here are 10 AppleScripts that you can assign keyboard shortcuts to using Quicksilver.

3. Drag and drop everywhere
This is often a problem that comes from working in Windows a lot, where drag-and-drop doesn't quite have the same power. However in Mac OS X, you can use it almost anywhere. Dragging folders onto open/save dialogs will make it display that folder. Dragging text selections onto icons in the Dock does all sorts of useful things. And you can just drag files onto "Choose File" buttons in web pages.

4. Change hidden settings with Terminal commands
Often developers choose not to include some settings in the preferences of an application in order keep things nice and simple for the user. Luckily, they often leave these hidden settings accessible via the Terminal. Although this will scare off a lot of people, being comfortable with the Terminal is really useful and it's the best way to get a higher level of customisation and enable hidden features on your Mac. Luckily, modifying preference files is one of the easiest things you can do in the Terminal - just paste in a line of code and hit return. Simple! Here are a list of Terminal commands that will work with every version of Mac OS X, and here are some ones just for Leopard.

5. Download VLC
VLC is a multipurpose media player that can play pretty much any movie file you throw at it. While Quicktime will serve you for most needs, VLC will handle anything that Quicktime struggles with, as well as stubborn DVDs and VIDEO_TS folders. Download it here.

6. Understand the concept of packages
In Mac OS X, packages are just folders disguised to look like single files. In fact, almost every application is a package. To look inside packages, just right-click on one and choose Show Package Contents. Why would you want to do this? Inside application packages are all the files it needs to run. Once inside, you can tinker about and change things. Here's a previous tip with a collection of things you can do, including changing the unexpectedly quit message, the iCal alarm message and the layout of System Preferences.

7. Quickly kill accidently opened applications
If you are clumsy like me, you will often accidently click the wrong icon in the Dock. Or maybe you occasionally want to stop iTunes opening up when you plug in your iPod. If you are quick enough, you can just right-click (Control-Click) on the icon in the Dock and choose Force Quit. If you are too late, pressing the Option key will change Quit to Force Quit so you can close the unwanted application even faster.

8. Make rectangular selections (Cocoa apps only)
This is one of the best tricks for saving time when you are moving round chunks of text. If you want to select a column in a table or remove the numbers from the start of each line in a list you would normally have to go through every line individually. This can be hugely time consuming if you have a long list. To get around this, just hold the Option key while making the selection. Now you can draw a box around the stuff you want to copy or delete etc. and not worry about having to select entire lines.

9. Learn some AppleScript
Don't be put off by the idea of a programming language - AppleScript is about as close to normal english as you can get. AppleScript's real power is it's ability to automate repetitive tasks - in fact Automator is basically just a visual way to create AppleScripts. The best way to get familiar with AppleScript is to download some example scripts, try and figure out how they work, and then try and extend them or customise them for your own needs. If you are looking for scripts, I've written loads of tips that use a small bit of AppleScript to solve a problem.

10. Get comfortable using the command line
While you might be fine pasting a single line into the Terminal to change some hidden settings, you might not be comfortable actually working from the command line. I guess the whole point of Mac OS X is that it is a pretty graphical interface placed over the command line, but in reality some things are faster from the Terminal, and some things aren't possible without it. Learning about using the command line requires a whole tutorial in itself so I won't go into it here. O'Reilly have a great series of tutorials for beginners, and OSXDaily have a list of common commands.

I've recently started using GeekTool a lot, and since I posted tips for displaying iCal events and Tweets on the desktop, I've found a few more cool things you can do.

Show Basic System Information
It is possible to use shell commands in GeekTool to display the computer name, operating system version, the amount of RAM and the processor details. This is useful if you have loads of the same model, or if you often remotely control other Macs.

To display this information, just open up System Preferences and click on GeekTool (download it first if you haven't already). Create a new entry, and change the type from File to Shell. Paste the following code into the box:

scutil --get ComputerName;
sw_vers | awk -F':\t' '{print $2}' | paste -d ' ' - - -;
sysctl -n hw.memsize | awk '{print $0/1073741824" GB RAM"}';
sysctl -n machdep.cpu.brand_string;

You might notice that each line of the code corresponds to a line of the output. In fact the code is actually 4 separate terminal commands. If you want you can delete or modify any of the lines and it won’t affect any of the others. Just make sure each line ends with a semicolon.

These details pretty much never change, so it's worth changing the refresh time to something very high. It is measured in seconds, so something like 100000 (about one day) should be alright. Once you adjust the font, colour and position, the result looks something like the screenshot below.

Show Free Disk Space
df is a command line utility for getting information on how much disk space you have free. The following command gets the output of the df command and converts it into a more readable format:

df -hl | grep 'disk0s2' | awk '{print $4"/"$2" free ("$5" used)"}'

Just add this into GeekTool in the same way as usual. "disk0s2" is the identifier for the hard drive. You can find out what yours is Disk Utility (located in Applications/Utilities). Just click on the hard drive in the list on the left and choose Get Info... from the File menu (Command-I). The Disk Identifier property is near the top of the info window.

The second part of the command is awk which rearranges the output. You can change this arround. Just make sure all text is inside double-quotes, and all variables (e.g. $2) are outside. $2 gives the capacity, $3 gives the used, $4 gives the free, and $5 gives the percentage used.

This one would fit quite well with the system info above, but it is likely to change more so you might want to keep it separate and have it refresh more often.

Display Album Artwork and Song Details of iTunes Currently Playing
I won't go into detail with this, because I don't have it set up on my system. This basically involves using AppleScript to get the details from iTunes. The song details are relatively straightforward to get, but the album artwork is a bit more complicated. Mac OS X Hints shows how to do the song details here, and the album artwork here.

Display a One-line Weather Forecast
Unfortunately this one is for US readers only (or people who want to know the weather in the US). The website Weather Underground gives a single line weather forecast that just compares today or tomorrow to the previous day. As usual, just create a new GeekTool entry, change the type to Shell and paste the following in the box:

curl -s http://www.wunderground.com/cgi-bin/findweather/getForecast?query=12345 | awk '/Today is/ || /Tomorrow is/' | textutil -convert txt -stdin -stdout -format html

Replace 12345 with your zip code, and you should have a weather forecast for your area. Running this takes a bit of time and system resources, so it's best to change the refresh rate to at least a few hours (about 10000).

Stop GeekTool preventing Sleep
You may have noticed that GeekTool prevents your Mac from going to sleep after the time period set in the Energy Saver section of System Preferences. The display will sleep, but the computer itself will never sleep because it is continuously performing tasks and Mac OS X doesn't think it is idle. This isn't really an issue for me, as I normally close the lid of my MacBook when I'm not using it, but I can see how this would be a problem for others. There is a solution explained over at Mac OS X Hints that uses an application called SleepWatcher to disable GeekTool as soon as the display goes to sleep.

As reported in TUAW yesterday, a reader named Ben G saw my recent tip for displaying iCal events and to do items on the desktop and took it one step further. Inspired by iCalBuddy, he has written a similar command line utility called twitterbuddy that instead displays the latest tweets by the people you follow. Getting this onto your desktop is pretty much the same process as with iCalBuddy.

Once you have downloaded twitterbuddy, double-click the install.command file to install it. To test it works, open up a new Terminal window and type in twitterbuddy -h. This should bring up the following list of options:

As you can see, typing twitterbuddy -u yourusername -p yourpassword -n 5 -t Tweets will display the last 5 tweets you have received, with the title “Tweets”. After perfecting your settings in Terminal, adding the command to GeekTool is easy. As with iCalBuddy, the only subtlety is that you have to use the full path, as shown below:

/usr/local/bin/twitterbuddy -u macosxtips -p ******** -n 5 -t Tweets

For help setting up GeekTool and formatting your output, check out the iCal on the Desktop tip, as everything is the same. Many thanks to Ali Rantakari, the deveoper of iCalBuddy and Benjamin Goering, the developer of twitterbuddy for all their hard work.

Also, if you want to, follow me on Twitter.

Apple released a new beta version of Safari yesterday, bringing a whole load of new features, as well as a couple of problems. Here are a few tips to help you get the most out of the new version and solve any teething problems you might have.


1. Download Safari 4 beta
As this is just a beta version, Apple doesn't include it in the automatic Software Update. To get the new version, head over to the Safari 4 beta page on the Apple web site. Bear in mind this will get rid of Safari 3, but there is an uninstaller included if you ever want to revert back.

2. Update your plugins
While most plugins for Safari should be fine with the new version, InputManagers are likely to need updating. 1Password has released an update, but you have to go to the 1Password app in your Applications folder to access it. Go to the Preferences and in the updates section, check the box that says Include Beta versions. Now when you check for updates it should download a version that works with Safari 4. Updates for Glims and Saft are already available from their respective sites, but as far as I know PithHelmet and SafariStand haven't been updated yet.

3. Safari breaks Xcode
This one is mainly for developers. If you are using the 3.0 version of Xcode, you will find that it crashes on launch once you have downloaded the Safari 4 beta. Just head over to the Apple Developer Connection to download version 3.1.2 of Xcode that works fine.

4. New keyboard shortcuts
Now Control-Tab will allow you to cycle through your tabs (as opposed to Command-Tab that cycles through applications). Don't worry if you were used to the old shortcut though, Command-Shift-Arrows still work.

5. Add the zoom button
The new zoom feature works just like Safari on the iPhone. Instead of just increasing the font size, it increases the size of images and other media too. You can access this from the View menu or with the Command-+ and Command-- shortcuts. Alternatively, choose Customize Toolbar from the View menu to add the zoom button to the toolbar.

6. Restore the old style tabs
One of the biggest changes visually is the new tabs, located along the top of the window. If you aren't a fan of this, a simple Terminal command will move them back to the old position. Just open up Terminal (in Applications/Utilities) and paste in the following line:

defaults write com.apple.Safari DebugSafari4TabBarIsOnTop -bool FALSE

To bring back the new tabs on top, just repeat the command with TRUE at the end. You will need to restart Safari for changes to take effect.

7. Disable search suggestions
Now the Google search box gives suggestions for your search as well as recent searches. To disable this, just use the following Terminal command in the same way as above:

defaults write com.apple.Safari DebugSafari4IncludeGoogleSuggest -bool FALSE

As before, repeat with TRUE at the end to bring back suggestions.

8. Bring back the old progress bar
Unfortunately, the new spinning progress indicator doesn't give you a good idea of how far the page has loaded. To bring back the old style, you have to use both of the following commands.

defaults write com.apple.Safari DebugSafari4IncludeToolbarRedesign -bool FALSE

This changes the progress indicator to a blue pie chart. To get the blue bar, now use the following command:

defaults write com.apple.Safari DebugSafari4LoadProgressStyle -bool FALSE

Repeat both commands with TRUE at the end to go back to the new style.

9. Disable bookmarks Cover Flow
If Cover Flow isn't your thing, you can get rid of it in the Bookmarks window by using the following Terminal command:

defaults write com.apple.Safari DebugSafari4IncludeFlowViewInBookmarksView -bool FALSE

Repeat with TRUE at the end to bring back Cover Flow.

10. Disable dimming in Top Sites zoom
When you choose a page in Top Sites, it zooms in to take up the whole page with a neat animation effect. To stop the page dimming during this, use the following Terminal command:

defaults write com.apple.Safari DebugSafari4TopSitesZoomToPageAnimationDimsSnapshot -bool FALSE

Repeat with TRUE at the end to revert back to the original behaviour.

11. Disable Top Sites
If, for some reason, you want to completely disable the Top Sites feature, use the following command:

defaults write com.apple.Safari DebugSafari4IncludeTopSites -bool FALSE

Repeating with TRUE at the end will enable Top Sites again.

12. Disable "fancy" URL suggestions
This is actually one of my favourite new features in Safari 4. When you are typing in a web address, suggestions are separated into Bookmarks, History and a Top Hit. If you prefer the old window, use the following command:

defaults write com.apple.Safari DebugSafari4IncludeFancyURLCompletionList -bool FALSE

Repeat the command with TRUE at the end to enable the fancy completion list again.

13. Add web sites to Top Sites
If you click the Edit button in Top Sites, it is easy to use the pins to force sites to stay in Top Sites. To manually add a site that isn't already there, open it up in a separate window, then drag the favicon (next to the address) over to one of the positions in Top Sites. You can also drag sites from your bookmarks to Top Sites.

14. Fix GrowlMail
Unfortunately GrowlMail will now cause Mail to crash. There is a quick workaround that involves putting GrowlMail into summary mode. Do this by using the following Terminal command:

defaults write com.apple.mail GMSummaryMode -int 2

Supposedly the next version of GrowlMail should fix this problem.

Recently I have been trying out different ways to display the current day's iCal events and to do items on my desktop. I wanted a way of quickly checking what I need to do that day without having to open iCal, Dashboard or any other application, and eventually I found a method I was happy with. The screenshot below shows how I have mine displayed, but it's pretty easy to customise it to your own needs. Here are the steps if you want to do it yourself.

1. Get GeekTool and iCalBuddy
To set this up you need to download two (free) applications. The first is GeekTool, a preference pane that allows you to display files, images and shell scripts on the Desktop. The second is iCalBuddy, a command line utility that lets you access events and to do items without having to open iCal.

Download GeekTool from here and install it by double-clicking on the preference pane. You can now access it by going to System Preferences and looking in the bottom row.

Download iCalBuddy from here and double-click it to unzip the folder. The installation is a little bit complicated. Open up Terminal (located in Applications/Utilities) and type cd followed by a space. Now drag the iCalBuddy folder onto the Terminal window and hit Enter. Finally, type sudo ./install.sh and hit enter. To test if everything is installed properly, try typing in icalbuddy eventsToday, which should bring up a list of today's events.

2. Set up GeekTool
At first, GeekTool's interface appears slightly confusing, but once you've played around with it for a little while you get the hang of it. Start by clicking New Entry in the bottom left. A new item called console should appear in the list of the left. To the right of that, change the popup menu from File to Shell, and type date in the command box. If you look on your desktop now, the date should be written in the top left. You can click and drag this around to where you want it, or you can type in the position in the bottom right of the GeekTool window. As you can see, the time only updates every 10 seconds. You can change this in the Refresh box above the Command box.

3. Change the appearance
If you have a dark Desktop background, you may find that you can't see the date. By default the date appears in an ugly plain fixed width font with a black text colour. To make this more visually appealing, click on the "Colors and Font" tab and adjust the settings. You can see my settings in the screenshot below. Obviously lighter text colours work better with darker desktop backgrounds and vice versa.

4. Format the date
The Shell option on GeekTool works just like the Terminal. If you type date into the Terminal and press enter, you should get exactly the same thing back as shown by GeekTool. Conveniently, the date Terminal command has a number of options to change the style of the date. As you can see, the default setting includes the time, time zone and year that I don't really want. The command for my preferred date format is date '+%a %e %B' which gives something like Wed 18 February. Apple has a list of formatting options here you can use to change it to whatever you want. You need to put a + at the start, followed by the symbols for the bits you want. You can but punctuation like commas between the symbols, and the whole thing has to be enclosed in single quotes.

5. Add today's iCal events
This is where the iCalBuddy application comes in. Create a new entry by clicking the button in the bottom left, and change the type to "Shell" as before. In the Command box type /usr/local/bin/icalBuddy eventsToday. This should bring up a list of today's events on the desktop. There are loads of customisation options for iCalBuddy, so I won't go through them all, but I'll show you mine. The command I use is:

/usr/local/bin/icalBuddy -nc eventsToday | sed -e "s/*/--/" | sed -e "s/!/!!/"

The -nc part removes the calendar name in brackets because all my events are in the same calendar. The sed -e "s/*/--/" part changes the * at the start of each event to a -- because I think it looks better. The "sed" and "awk" commands are really useful for customising the output, but I won't go into much detail here. Just do a Google search for a tutorial if you want more information. For the different iCalBuddy customisation options, check out the man page.

One customization to note is the "eventsToday+NUM" option. Replacing eventsToday with eventsToday+3, for example, will display the events for the next three days in separate sections titled by the date.

6. Add to do items
To do items work in pretty much the same way as the iCal events. The command to use is /usr/local/bin/icalBuddy uncompletedTasks. Similar to before, the command I use is:

/usr/local/bin/icalBuddy -nc uncompletedTasks | sed -e "s/*/--/" | sed -e "s/!/!!/"

The only difference to the modifications before is that I also double up the ! that appears for overdue uncompleted tasks.

7. Add some titles
If you just want GeekTool to display some text, the easiest way to do it is to use the echo command. Just create a new entry and use the command echo To Do List to make it display "To Do List" on the Desktop.

8. Set the Refresh rate
The next thing to do is to set a suitable refresh rate for each item. It is worth noting that these command take very little system resources, and having them all update every 10 seconds produces absolutely no decrease in performance whatsoever that I've noticed. However, in principle you should only really make them refresh as much as you need them too. I've set all mine to update once an hour (3600). This means that the worst case scenario is that the information is wrong for up to an hour between midnight and 1am each night. If you like having the time displayed in the date command, you probably want that to update every second.

8. Make it pretty
Finally, you just have to change the font and colour of each entry and position them somewhere you want on the Desktop. I went for the far left as it's a place guaranteed not to get covered up by icons.

9. Go crazy
There are hundreds of things you can do with GeekTool, and it's definitely worth trying them out and seeing what you like. In the end, I only kept the iCal events and to do list, but you may like having constant updates of your uptime, running processes, CPU use, local weather maps, IP address, current iTunes track etc. Check out the following articles for more details:

Ultimate GeekTool Setup - Pimp Your Desktop
Monitor your Mac and more with GeekTool
Geektool and Bash One-Liners

Most Mac users should be familiar with disk images, and if you aren't, you probably use them all the time without even realising. Their most common use is for distributing applications across the internet. If you download an application like Firefox or VLC for example, they come as a .dmg file. Double-clicking this file will mount a disk image with the application inside on your desktop.

Disk images have far more widespread uses than this though. They can be used to create a exact copy of any CD, DVD or hard drive and turn it into a single .dmg file. You can then transfer this file around, and then simply double-click on it to mount the disk image. The most common uses of this are to create backups, to create a file for burning to CD/DVD, or to transfer the entire contents of a hard drive from one computer to another.

Unfortunately, the dmg type disk images that Mac OS X uses are not really Windows friendly. The cross-platform standard for disk images is the ISO format. These can be created on your Mac, and can be read by any Mac or Windows PC. This is especially useful if you want to burn a CD or DVD and your Mac doesn't have a burner but your PC does.

The first step in creating an ISO image is to make a folder of all the things you want to be in your disk image. Next, open up Disk Utility, located in the Utilities folder in the Applications folder. In Disk Utility, choose "New... Disk Image from Folder" from the File menu, or hit Command-Shift-N. Choose your folder, and then select a name for your image. Choose "DVD/CD master" from the Image format pop-up menu, and leave the Encryption as none. Click Save, and you're almost done.

You have created an ISO image, but strangely Disk Utility gives it the .cdr extension instead of the standard .iso extension. To avoid confusing Windows PCs, just rename your image with the .iso extension and you're done.

If you already have a normal Mac .dmg disk image, it's just as easy to convert it to .iso using Disk Utility. Just select Convert from the toolbar or the Images menu. Use the same settings as above, and remember to change the file extension to .iso.

For those of you who love the command line, you can convert disk image formats using hdiutil. This has the benefit of not requiring you to change the extension, but probably won't work out any quicker as the process is so straightforward in Disk Utility.

To convert from DMG to ISO, open up Terminal (in Applications/Utilities) and type:

hdiutil convert /path/to/image.dmg -format UDTO -o /path/to/newimage.iso

Replace the two paths with the location of the image and the place you want to save the new image. For example I would use /Users/matt/Desktop/image.dmg. To avoid mistakes, you can just drag the image to the Terminal and it will enter the path for you.

To convert from ISO to DMG, just use the following instead:

hdiutil convert /path/to/image.iso -format UDRW -o /path/to/newimage.dmg

In my opinion, the best addition to Mail.app in Leopard are data detectors. This feature means that Mail will automatically pick out dates, times and addresses so you can add events to iCal or view a map with just a couple of clicks. For iCal events, Mail even recognises relative dates like "tomorrow" and automatically enters this information when creating a new event.

To use the data detectors feature, simple hold your mouse over a date or time in an email message. A dashed box should appear around the item, with an arrow that you can click to bring up a drop-down menu. The two options available are "Create New iCal event" and "Show This Date in iCal". If you create a new event, a dialog box just like the one in iCal pops up, ready filled with the information. This all happens within Mail, so there is no need to even open iCal.

While this is a great timesaving trick, unfortunately the Mail dialog lacks some of the features that the iCal one has. You can only add a single alarm, and you can't add attendees or attachments. However, it is still possible to use data detectors to fill out your event information and have access to these more advanced options.

Simply hold down the Option (alt) key when clicking on the data detector drop-down arrow. The menu item should now read "Create New Event in iCal". Selecting this will load up iCal and create a new event with the information in the Mail message.

If you already started creating an event in Mail, and then decide you want to add multiple alarms or attendees, simple hold down the Option (alt) key. The "Add to iCal" button at the bottom should change to "Edit in iCal", allowing you to make the changes you want.

Enable Data Detectors in iChat
Apple also built data detector functionality into iChat, but chose to disable it for some reason. Luckily, enabling it again can be done by a simple Terminal command. Start by opening up Terminal (/Applications/Utilities). In the window that appears, paste the following line, and hit enter.

defaults write com.apple.iChat EnableDataDetectors 1

Next time you open iChat, data detectors should be enabled. To disable them again, repeat the command with a 0 at the end instead of a 1.

Disable Data Detectors in Mail
If you never use data detectors, you might want to disable them. This can be done using the following Terminal command:

defaults write com.apple.mail DisableDataDetectors YES

Next time you open Mail, data detectors shouldn't appear. If you want them back, just repeat the command with NO at the end.

This tip was written by 11 year old Alex Hwang. Be sure to check out his blog, as he's recently posted an application that allows you to customise your Dock without having to play around with Terminal commands...

Since Mac OS X 10.4 Tiger, the amazing operating system has included many built in things. One of the many great things included with Mac OS X is called TTS (text to speech). I'll be covering an easy way to dive into text to speech. All you have to do is fire up Terminal.app (/Applications/Utilities/Terminal.app) and type in:

say 'text to say with no quotes'

So if you type in:

say Hello World

And hit return, then (as long as your speakers are turned on) your computer will 'say' hello world to you! A more advanced way to do this is to type in:

osascript -e 'say "some text" using "some voice"'

You can check the voices your system has in System Preferences in the Speech pane under the Text to Speech tab. You might have to select “Show more voices” at the bottom to get the full list.

[Matt adds: For any Cocoa application (Safari, TextEdit, etc.) there is a "Start Speaking Text" option under the Services menu (in the Application menu) that will speak your selection in the currently selected system voice. Great if you want a web page or long piece of text read to you. You can even assign a keyboard shortcut to it in the "Keyboard and Mouse" section of System Preferences. Also, since Leopard, Apple has added a new voice, Alex, which is much more realistic than the usual "robot" sounding voices that are available.]

I've noticed a lot of recent articles around the web about taking screenshots on a Mac. There's just the odd tip here and there, so I thought I'd do a complete guide. If you are familiar with taking screenshots, you might want to scroll down to the bottom, where there are some more advanced tips.

Keyboard Shortcuts

The quickest way to take a screenshot is to use a keyboard shortcut. Annoyingly, these aren't particularly intuitive. There are two main ones:

Command-Shift-3 - Take a screenshot of the entire screen.
Command-Shift-4 - Allows you to click and drag around the area you want a shot of.

Each of these will save a file to the desktop named Picture 1.png, or a higher number if that file already exists.

Now there are a few extra things you can do. If you press Space after pressing Command-Shift-4, you will notice that the cursor changes to a picture of a camera. You can now just click on a window, icon, widget or almost any other interface element to take a screenshot of it. You can also add Control into the keyboard shortcut to put the image in the clipboard instead of saving it to the desktop. For example, pressing Command-Control-Shift-3 would allow you to then paste the image into another document.

The Grab Application

If you can never remember keyboard shortcuts, the Grab application is for you. It is located in Applications/Utilities and it has many more options for screenshots than the keyboard shortcuts do. The two main advantages (in my opinion) are timed screenshots and being able to change the pointer type.

You can create a timed screenshot by going to the Capture menu, or by pressing Command-Shift-Z. Using this, you can achieve screenshots that are supposedly “impossible”. One example is the login window.

To change the pointer type, go to the Preferences. See the image below for the different options.

Disable Shadow

If you use the Command-Shift-4 Space method to take a screenshot of an entire window, you will find that the shadow is in the screenshot. This was added in Leopard because without the shadow, windows don't actually have a border if they have no scrollbars. However, if you prefer no shadows, you can disable them with a Terminal command. Simply open up Terminal (located in Applications/Utilities), paste in the following line and hit return.

defaults write com.apple.screencapture disable-shadow -bool true

Afterwards you will need to log out and in again for changes to take effect. To enable shadows again, simply repeat the command but with false at the end. The two images below show a before and after shot.

Change Image Format

The default image format for screenshots is png, which gives a nice, high quality picture. However you can change this if you want. As before, use the following Terminal command:

defaults write com.apple.screencapture type png

Simply replace png with your file format of choice. The available options are jpg, tiff and pdf. Changing to jpg gives a lower quality but smaller file. Some people prefer this for quick snaps, but others dislike the slightly blurry results it gives. As before, log out and in again for changes to take effect.

Advanced Screenshot Applications

If widgets are your thing, Screenshot Plus will probably be the method of choice for you. It's free, and allows you to do everything that you can achieve with keyboard shortcuts. It also allows you to view a preview image, before saving it to the desktop or importing it into Preview.

If you really want to go all out on your screenshots, you might want to consider buying an application like Snapz Pro. It allows you to do all of the things above, as well as record movies of your screen.

Finally, if you want to get screenshots of long webpages that don't fit on the screen, Paparazzi! is your solution. It gives allows you to set the size of the image, set a delay, choose the file name and choose the file format. Of course, if you want a PDF of the web page, that functionality is already built into Mac OS X.

UPDATE: Many people in the comments have pointed out that I forgot Skitch. After playing around with a it a bit this morning, I have to say I agree, it’s probably the best screenshot application available at the moment. For those interested, there’s a great 3 minute introduction video available.

Also, the MacTipper Blog pointed out one more thing I forgot. Using another Terminal command, you can change the default save location to somewhere other than the Desktop. The command is as follows:

defaults write com.apple.screencapture location /Full/Path/To/Folder

For full instructions, check out the MacTipper Blog.

Back in March I did a tip listing 15 Terminal Commands for Hidden Mac OS X Settings. Since Leopard has been released, there are a whole load of new ones so I thought I'd do another list.

In general, these will only work with Leopard. I have slipped in a few that will work with Tiger, but you should check out the old list for commands that will definitely work.

If you don't already know, here are some quick instructions of how to use them: You'll find Terminal in the Utilities folder within the Applications folder. To carry out any of the following commands you will need to copy/paste or type in the line of text then hit enter. Most of the commands change settings that can't be done through the application or system preferences.

For the most part, applications will need restarting before changes take place. For the Dock and the Finder, it isn't obvious how to do this. The easiest way is to type a second command into the Terminal afterwards. Type "killall Dock" followed by return for all the Spaces, Stacks and Dock commands. "killall Finder" followed by return for all the Finder related ones.

Spaces

defaults write com.apple.dock workspaces-edge-delay -float 0.5

Changes the delay when dragging windows off the edge of the screen to other spaces. Default value is 0.75.

defaults write com.apple.dock workspaces-wrap-arrows -boolean NO

Disables the wrap-around when using Control-Arrow keys to changes Spaces. To enable again, repeat with YES at the end.

Stacks

defaults write com.apple.dock persistent-others -array-add '{ "tile-data" = { "list-type" = 1; }; "tile-type" = "recents-tile"; }’

Creates a Recent Applications stack in your Dock, that you can change to display other recent items. To remove it, use the command defaults delete com.apple.dock persistent-others but be warned, this will remove all your stacks.

defaults write com.apple.dock mouse-over-hilte-stack -boolean YES

Adds a Mouse Over gradient to items in your stacks. To disable, repeat with NO at the end.

Dock

defaults write com.apple.dock no-glass -boolean YES

Change to 2D Dock. To change back to 3D, prepeat with NO at the end.

defaults write com.apple.dock tilesize -int 256

Allows you to increase the size of the Dock past the maximum allowed by the slider in System Preferences. Don't go larger than 256. Use the slider in System Preferences to shrink the Dock down again.

defaults write com.apple.dock largesize -int 512

Allows you to increase the Dock magnification past the maximum allowed by the slider in System Preferences. Don't go larger than 512. Use the slider in System Preferences to shrink the Dock down again.

defaults write com.apple.dock enable-spring-load-actions-on-all-items -boolean YES

Makes all items in the Dock spring loaded. For example, hold a file over an application and it will open or come to the front so you can drop the file onto a specific window. Repeat with NO to reverse.

Finder

defaults write com.apple.finder FXListViewStripes -bool FALSE

Removes the stripes in list view. Repeat the command with TRUE to reverse.

/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain local -domain system -domain user

Resets the "Open With" menu, clearing duplicates. The command is different from the one in Tiger.

defaults write com.apple.finder _FXShowPosixPathInTitle -bool YES

Changes the title of a window to its full path. Repeat with NO to reverse.

Spotlight

sudo chmod 0 /System/Library/CoreServices/Spotlight.app

Disables the Spotlight icon. Type "killall Spotlight" for changes to take effect. To re-enable it, type 755 instead of 0.

Time Machine

sudo defaults write /System/Library/LaunchDaemons/com.apple.backupd-auto StartInterval -int 7200

Changes Time Machine's backup interval. Requires an administrator password. Default value is 3600 (seconds).

iCal

defaults write com.apple.iCal IncludeDebugMenu YES

Enables the Debug menu in iCal, just like the Safari one. Repeat with NO at the end to disable.

Safari

defaults write com.apple.Safari DebugConfirmTossingUnsubmittedFormText NO

Disables the warning given when closing a window with text entered into a form that you haven't submitted. To bring back the warning, repeat the command with YES.

Check out this article for more Safari 3 tips.

Menubar
Changing the menubar will require an administrator password and you will need to restart the Mac for changes to take effect.

sudo defaults write /System/Library/LaunchDaemons/com.apple.WindowServer 'EnvironmentVariables' -dict 'CI_NO_BACKGROUND_IMAGE' 1

Remove translucency in menubar, turns it white.

sudo defaults write /System/Library/LaunchDaemons/com.apple.WindowServer 'EnvironmentVariables' -dict 'CI_NO_BACKGROUND_IMAGE' 0

Removes translucency in menubar, turns it grey.

sudo defaults delete /System/Library/LaunchDaemons/com.apple.WindowServer ‘EnvironmentVariables’

Reverts back to default translucent menubar.

All Applications

defaults write -g PMPrintingExpandedStateForPrint -bool TRUE

Applications use the expanded Print dialog by default. Similar to the expanded Save dialog in earlier OS versions. Repeat with FALSE to reverse.

When you double-click a file it will open in the default application, which is fine for most situations. Often, each file format corresponds to a single application. Word documents open in Microsoft Word, MP3s open in iTunes and movies open in Quicktime Player. But there are times when you might want a file to open in a different application. For example, you might want a image to open in Photoshop rather than Preview, or a Word document in TextEdit instead of Microsoft Word. In this situation, you have a few options.

Firstly, if the application is in the Dock, you can simply drag the file onto its icon in the Dock. Alternatively you can open up the application first, and choose "Open" form the File Menu. A third method is to use the "Open With" menu. You will find this by right-clicking (Control-clicking) on the file and looking near the top of the contextual menu. Within the Open With submenu you will find every application that can open the file, as well as an "Other" option.

When you use the Open With menu, it is a "this time only" thing. Next time you double-click on the file, it will open with the default application again. To change the default application, bring up the menu as before, but hold down the Option key before choosing the application. The menu should change to "Always Open With".

When you use the Always Open With menu, it is a "this file only" thing. To apply a new default application to all files of that format, you can use the Get Info window located in the File Menu. In the Open With section, set the new application and click the "Change All" button.

To reset all of your files to open with the original default application, you need to delete a certain file. Go to your user folder, and navigate into the Library folder then into the Preferences folder. Find the com.apple.LaunchServices.plist file, and drag it to the Trash. Alternatively, drag it to the Desktop if you think you might change your mind and want to put it back later.

Over time, you may find that the Open With menu gets cluttered with duplicates, older versions or applications you thought you deleted long ago. To get rid of these, you need to use Terminal. Open up Terminal (from Applications/Utilities) and paste the following line:

/System/Library/Frameworks/ApplicationServices.framework/Frameworks/LaunchServices.framework/Support/lsregister -kill -r -domain local -domain system -domain user

Press return and your Open With menu should have been cleaned up to only include the most current applications.

The Safari 3 public beta has been out for a while now, and will be included with Leopardwhen it comes out. If you haven't tried it out yet, you can download it for free from the Apple site. The following tips include things that will be useful to the average user as well as some more interesting tricks for more experienced users.

Merge Windows
Safari 3 now allows you to drag and drop tabs. You can drag a tab off the bar to create a new window or drag it onto an existing window to add it. You can also use this to rearrange the order of your tabs. If you have lots of open windows each with different numbers of tabs, there is an easier way to get them all into one instead of dragging and dropping. In the Window menu you will find the "Merge All Windows" command. This will instantly combine all your open windows into one tabbed window.

Enable Web Inspector
The Web Inspector allows you to easily see how the source code creates the web page. You can inspect various elements of the web page and view their style, metrics and properties. If you select an element in the inspector window, it will briefly be outlined in red on the web page.

To enable the Web Inspector, open up Terminal (located in Applications/Utilities), type the following line and press return:

defaults write com.apple.Safari WebKitDeveloperExtras -bool true

Now quit and re-open Safari. Open a web page and right-click (Control-click) anywhere. You should see a new "Inspect Element" item in the list.

Pie Chart Loader
Normally Safari indicates how far a page has loaded using the address bar as a progress bar. The box gradually fills with colour from left to right. If you want, you can easily change this to the pie chart type indicator that is used in Mail. Again, open up Terminal (in Applications/Utilities), type the following command and press return:

defaults write com.apple.Safari DebugUsePieProgressIndicator -bool true

To switch back to the old progress bar, simply repeat the above command with false instead of true.

Bookmark all tabs
This new feature obsoletes the tip I wrote last month about bookmarking all tabs in Safari 2. Doing this is now much simpler - you just need togo to the Bookmarks menu. Here you should find an item that says something like "Add bookmark for these 4 tabs...". The default settings creates a bookmark called "Saved Tabs" in the bookmarks bar. This is actually a folder of your tabs, but it has been set to automatically open all the pages in tabs when clicked.

Others
There are loads of other new features in Safari 3 that are well known or don't really require any explanation. For example, the find command now dims the page and highlights the words you searched for, web history now indexes the text content of the page for easier searching, you can reopen the last closed window or the windows from your last session and all text fields are resizable.

For all of these tips you will need know the password to an administrator account. You can check whether an account is an administrator in the Accounts section of System Preferences.

1. Add a message to the login window
You can add a string of text above the list of users in the login window. To do this, start by opening up Terminal. This is located in the Utilities folder, inside the Applications folder. Once it has loaded, paste in the following line and press return:

sudo defaults write /Library/Preferences/com.apple.loginwindow LoginwindowText "Hello There”

Replace "Hello There" with your text. To remove the text, type the following line:

sudo defaults write /Library/Preferences/com.apple.loginwindow LoginwindowText “”

2. Hide accounts
If you find yourself with an overly long list of users in the login window or you just want to get rid of that annoying scroll bar down the side, you can stop accounts appearing in the login window.

Start by go to the Accounts pane in System Preferences, and find the "short name" of each user you want to hide. Once you have these, open up Terminal and enter the following:

sudo defaults write /Library/Preferences/com.apple.loginwindow HiddenUsersList -array-add shortname1 shortname2 shortname3

Replace shortname1 2 and 3 with the short names of the user accounts you wish to hide. You can hide as many as you like, just separate each with a space.

To make a hidden name appear again, type the command with no names in it, therefore resetting the list of hidden users.

sudo defaults write /Library/Preferences/com.apple.loginwindow HiddenUsersList -array-add

Notice that doing this adds an extra option to your login window - "Other..." When you select this, you will be presented with text boxes to enter a username and password.

If you aren't running OS X 10.4, this doesn't work. Another option is to replace the list of users with username and password text boxes. Go to the Accounts pane in System Preferences and click on Login Options. There you will find an option to display the login window as name and password fields. This isn't as pretty, but saves time if you have lots of users, and is also more secure.

3. Change the Apple logo
You can replace the large Apple logo that appears at the top of the login window with any tiff image that is 90x90 pixels. In the Finder, choose Go to Folder from the Go menu or press Command-Shift-G. In the dialog box that appears, type the following line:

/System/Library/CoreServices/SecurityAgent.app/Contents/Resources/

A folder called Resources should appear. Here you will find an image called applelogo.tif. You will need to create a copy of this file, just in case you ever want to revert back to it. The easiest way to do this is to hold the Option key and drag it to a safe place (like your Documents folder). Now, rename you new image "applelogo.tif" and drag it to the Resources folder to replace the old file. You will be asked to type in an administrator password.

To change back to the Apple Logo, just drag the copy that you made back to the Resources folder.

4. Get useful system stats
The name of you Mac is displayed in the login window below the words "Mac OS X". Since Mac OS X 10.4.3, you can click on the name of your Mac to show different statistics about your machine. Each time you click, it will cycle through different bits of information that are particularly useful when troubleshooting problems.

The order of the statistics are as follows:

One click: Your OS X version number (e.g. Version 10.4.9)
Two clicks: Your OS X build number (e.g. Build 7M271)
Three clicks: Your mac's serial number (e.g. WN1511LHKNW)
Four clicks: Your mac's IP address (e.g. 196.254.0.1)
Five clicks: The status of any networked account
Six clicks: The date and time (e.g. Saturday, January 20 2007 4:02:31 AM GMT)
Seven clicks: Back to where you started, the name of your computer.

So you click a few times and set the information line to your favourite thing, but next time you log in, it has changed back to the name of your mac. To change the bit of information that appears first, you need to do a bit of tinkering in the Terminal (Applications/Utilities). Open Terminal and type the following command:

sudo defaults write /Library/Preferences/com.apple.loginwindow AdminHostInfo HostName 

Depending on which piece of information you want displayed, replace HostName with one of the following:

SystemVersion 
SystemBuild 
SerialNumber 
IPAddress 
DSStatus 
Time 

After doing this, hit return, and the next time you view your login window the information you chose will be displayed. To change it back to normal, simply repeat the command with HostName at the end.

5. Change the background image
There are ways to change the background image by replacing the Aqua Blue image, but that is slightly crude. A better way to do it is using the Terminal. Type the following command and press return:

sudo defaults write /Library/Preferences/com.apple.loginwindow DesktopPicture /Users/Shared/mynewbackground.jpg

The last part, /Users/Shared/mynewbackground.jpg is the location of the image you want to use. You don't have to type it out. Just paste the command as far as DesktopPicture and put a space after it. Then find your image in the Finder, and drag it onto the Terminal window. The address to your image should just appear. As far as I can tell, you have to place the image in a place that all users have access to (the shared folder is a good place).

To change back to the normal Aqua Blue image, type the following command and press return:

sudo defaults write /Library/Preferences/com.apple.loginwindow DesktopPicture /Library/Desktop\ Pictures/Aqua\ Blue.jpg 

Over the past few weeks, lots of people have been contacting Mac OS X Tips asking how to reset a forgotten Mac OS X user account password. Depending on the circumstances, this task could take 5 minutes or could even be completely impossible. Here is a run through of the different ways you can reset an account password depending on the type of account, whether FileVault is enabled and whether you have the Mac OS X Install Disc.

If you still know the Administrator Password
If you still know the password to an administrator account, it is very simple to reset any standard or managed user's password. While logged in as the administrator, open up System Preferences and click on the Accounts section. All the accounts on the computer should be listed down the left hand side. Under each account name it should say Admin, Standard or Managed. If the lock at the bottom of the window appears locked, click on it to allow changes to the preferences.

The next step is to select the user whose password you want to change and click on the Reset Password button. Enter the new password and click Reset Password. If you have created multiple Administrator accounts, you can use this method to reset their passwords too, as long as you know the password for the original administrator account.


Resetting an Administrator Password
Obviously, if you don't have access to an administrator account, you can't carry out any of the above steps. If you have forgotten the Administrator password or you can't log into your Mac at all, you will need to use the Mac OS X Install Disc.

Enter the Mac OS X Install Disc that is the closest version to that running on the Mac. For example, if you are running Mac OS X 10.4 Tiger, you should enter the Tiger install disk, not any earlier ones. Restart the computer, and hold the C key as it starts up. This might take longer than usual, and you can release the C key as soon as the Apple logo appears on the screen. When the window appears, choose your language and click the right arrow.

The next step depends on what version of Mac OS X you are using. For Tiger (10.4), choose Reset Password from the Utilities menu. For earlier versions, choose Reset Password from the Installer menu.

Choose your Hard Drive from the top and then choose the Account from the drop down menu. Be careful not to select System Administrator, as this is actually the root user, not the administrator account on your Mac. Now enter the new password, click Save, quit the Installer and restart the computer.

Note that there are a few issues with this method. Firstly, it does not reset your keychain password. You will have to do this separately. Secondly, do not attempt this if you have FileVault enabled. To reset an FileVault protected account, you need the master password.

Resetting a FIleVault Protected User's Password
If you have enabled FileVault to encrypt your Account, you need to know the master password that you set when you enabled it. This is the password that the administrator should know that allows you to reset any password on the computer. If you have forgotten the master password, unfortunately your data is lost forever.

If you know the master password, start by attempting to log into your account. When you get the password wrong three times, you will be able to click "Forgot Password". Now you will have to enter the master password and then a new login password for your account.

If you have lost the Mac OS X install Disc
If you have lost the install disc, don't try and use one from an earlier version as this might permanently block you out of your account. You really have two options: Firstly, you could buy a new copy of Mac OS X (try eBay). Secondly, there is a way of resetting an administrator password without the disc if you are running Mac OS X 10.4 Tiger. Note: Do NOT do this with a FileVault protected account, or your data will be lost forever.

First, note the short name of the account. This is the same as the name of its home folder, but not necessarily the name that appears in the login window. Restart your computer, and while it is starting up, hold Command-S. This will start up your Mac in Single User Mode. Once it has started up, you will need to enter three lines of code. Enter sh /etc/rc and press return. Then enter passwd yourusername and hit return. Now you will have to enter a new password twice. What you type won't appear on screen, but it is working. Once you have done this, type reboot and hit return.

This is the same as the Install Disc method in that it doesn't reset your Keychain password. You will have to do this separately.

If you have ever used Spotlight to search for a phrase within a PDF document, you may have encountered the annoyingly high level zoom in Preview.

When you click on the PDF in the Spotlight results, it opens up in Preview with the search term highlighted throughout the document. This is pretty useful, however the PDF is actually zoomed in 280 percent. This means you can read the word you searched for pretty easily, but you can't see anything else.

Luckily, by changing one line in the Preview preferences, you can change the zoom level to something less extreme. The easiest way to do this is using the Terminal.

First, quit Preview if it is running and open up Terminal from the Utilities folder in the Applications folder. Type the following line and press return:

defaults write com.apple.Preview Preview -dict-add PVPDFSpotlightSelectionSize 10

The 10 at the end corresponds to a 100% zoom level. By default, this number is set to 28, or 280% zoom. If you want some zoom, but not quite as much, try a number like 15 for 150% zoom.

If you don't want to use the Terminal, or you are curious to see what the command actually does, you can open up the preference file in Property List Editor (which you will only have if you have installed the Developer Tools from the Mac OS X install Disk). Go to your user folder and navigate to Library/Preferences and open up com.apple.Preview.plist using Property List Editor.

Use the expansion Triangles to navigate to Root/Preview/PVPDFSpotlightSelectionSize. Here you can see the number is 28 (or 10 if you have already changed it in the Terminal).

In Mac OS X many dialog boxes slide out of a window's title bar and are attached to that window rather than being on their own. These dialog boxes are know as "sheets" and can be anything from Open/Save dialogs to the Customise Toolbar settings. They are attached to a certain window to show that they are associated with that particular file or application. If you can't remember seeing this before, open up a TextEdit file and choose Save As.

The sliding animation may be pretty, but it can waste a fair amount of time if you are opening and closing sheets all day. You can speed this up and make your Mac feel much snappier by using a simple Terminal command to reduce the amount of time taken to display the animation.

Launch the Terminal (located in Application/Utilities) and type the following command:

defaults write NSGlobalDomain NSWindowResizeTime 0.001

The number at the end is the length of the animation in seconds. With it set to 0.001, sheets appear pretty much instantly. The default is 0.2, so type the command with 0.2 at the end to return your sheet animation to normal.

For fun you can try higher values. This allows you to see just how detailed the animation is. Type the command with 2 at the end and load up TextEdit. Resize the window to as small as possible before selecting Save As from the File menu. You'll see the sheet jump up out of the window then gently fall into place.

One of the comments on the Terminal Commands tip pointed out something I have never heard of before. Although it is entirely useless, (a lot of the stuff on this site is) I thought it was a nice trick:

They mentioned the killall Dock thing... if you hold shift and collapse a window it goes slowly into the dock. if you do a killall Dock command in the terminal while it's collapsing, the window freezes in it's squished state, while still allowing you to scroll in it and click links (although the links will be in their original location).
SleepingInsomniac | Homepage | 03.21.07 - 4:42 am | #

This is great fun, and also a little weird. As mentioned, you will need to press Shift while clicking minimize to slow things down and give you enough time to run the command. Have Terminal open with "killall Dock" ready typed so you just have to press enter. When the Dock relaunches, your currently minimizing window gets stuck half way, but is still treated like a normal window. Drag it around, scroll up and down, browse web pages. It's not perfect however - as SleepingInsomniac notes, the links on web pages are still where they were before you minimized, making things a bit confusing.

Check out the image below to get an idea of what it looks like.


To get your windows back to normal you just need to close (Command-W) and reopen them.

Thanks to SleepingInsomniac for this!

There is a huge amount of hidden settings for Mac OS X and its applications that aren't accessible from preferences dialog boxes or the System Preferences. Applications such as Tinkertool and Mac Pilot allow you to access some of these, but the real flexibility is from the Terminal. From here it is possible to edit any preferences file for any application on your Mac.

You'll find the Terminal in the Utilities folder within the Applications folder. To carry out any of the following commands you will need to copy/paste or type in the line of text then hit enter. For the most part, applications will need restarting before changes take place. For most applications you can just quit and open them again, and for the Finder you can use the Force Quit dialog, just log out and log in again or type "killall Finder" into the terminal after the command.

Feel free to add any of your favourites in the comments.

1.

defaults write com.apple.Dock showhidden -bool YES

Makes hidden applications' dock icons translucent. NO to reverse.

2.

defaults write com.apple.iTunes invertStoreLinks -bool YES

Normally the arrows next to artists and albums in your iTunes library search the iTunes store when you click them. This command changes them so that clicking will search your iTunes library instead. Put NO at the end to reverse.

3.

defaults write com.apple.dashboard devmode YES

This allows you to drag widgets out of Dashboard onto the desktop. Requires the dock to be relaunched to take effect, so type "killall Dock" and press enter. Now, if you click and hold onto a widget in the dashboard and press F12 to return to the desktop, the widget won't disappear with the rest. Put NO at the end to reverse.

4.

defaults write com.apple.mail PreferPlainText -bool TRUE

Forces all mail to be displayed as plain text. Replace TRUE with FALSE to reverse.

5.

defaults write -g NSNavPanelExpandedStateForSaveMode -bool TRUE

Sets expanded save dialogs as default (showing column/list view of folders rather than a drop down menu). Replace TRUE with FALSE to reverse.

6.

/System/Library/Frameworks/ScreenSaver.framework/Resources/ ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -background

Displays the currently chosen screen saver to be shown as the desktop background. Press Control-C or Command-. to stop. More details here.

7.

defaults write /Library/Preferences/com.apple.loginwindow AdminHostInfo SystemVersion 

Displays useful system stats in the login window. More details here. Replace "SystemVersion" with one of the following for different stats:

SystemBuild 
SerialNumber 
IPAddress 
DSStatus 
Time
HostName

8.

sudo defaults write /Library/Preferences/com.apple.loginwindow HiddenUsersList -array-add shortname1 shortname2 shortname3

To remove accounts from the login window type this command with the short name of each account you wish to remove. More details here.

9.

com.apple.frameworks.diskimages skip-verify TRUE

Skip disk image verification. Potentially risky, use with disk images from trusted sources. Replace TRUE with FALSE to reverse.

10.

defaults write "Apple Global Domain" AppleScrollBarVariant DoubleBoth

Puts double scroll arrows at both ends of scroll bar. Use Appearance pane in system preferences to reset.

11.

defaults write com.apple.CrashReporter DialogType none

Disables the unexpectedly quit dialog that normally appears when an application crashes. Replace "none" with "prompt" to enable again.

12.

defaults write com.apple.Safari WebKitHistoryItemLimit 2000

and/or

defaults write com.apple.Safari WebKitHistoryAgeInDaysLimit 30

Sets the history limit in Safari to a certain number of items and and/or a certain age.

13.

defaults write com.apple.finder AppleShowAllFiles TRUE

Shows hidden files in the finder. Replace TRUE with FALSE to hide hidden files again

14.

defaults write com.apple.safari IncludeDebugMenu 1

Enables the debug menu in Safari. Type again but with 0 instead of 1 at the end to disable.

15.

defaults write com.apple.dashboard mcx-disabled -boolean YES

Deactivates Dashboard. Requires the dock to be relaunched to take effect, so type "killall Dock" and press enter. Replace YES with NO to enable again.

This tip is quite a geeky one, but nothing in it is too tricky at all. It has no real serious purpose, but it will make your Terminal windows look pretty and help you get familiar with Terminal's settings if you aren't already.

Many Terminal users will already know how to change the colour and transparency of Terminal windows. The most basic method is to choose the Terminal menu, select Window Settings (or press Command-I). This brings up the Terminal Inspector. Choose color from the drop down menu, and you will be presented with all the customisation options.

There are some predefined colour schemes, such as the popular green on black, or you can make your own. It is also possible to set an image as the background, and choose the transparency of the window.

It is also possible to create colour schemes using different methods, such as the one outlined in this Macworld Article.

To set a colour scheme as the default, click the button at the bottom of the Terminal Inspector.

But what if you want multiple colour schemes, or you want to send one to someone else? Luckily you can save these settings simply by saving the terminal window.

Choose all your colours and settings as above, then click the File menu and choose Save As. Navigate to Library/Application Support/Terminal. If you don't have a Terminal folder in Application Support, create one. Save the file here with a name like "colour-scheme1.term".

Now, a Terminal window with the saved settings can be opened by choosing File --> Library --> colour-scheme1. To save one of these files as the default, go to the Terminal preferences and select "Open a saved .term file when Terminal starts" then select your chosen file.

Here are a few ready made colour schemes for you to download.

As an extra quirk, you can make Terminal choose a random colour scheme using a handy applescript created by Daniel Jalkut. It can create some pretty horrible combinations, but it does contain and algorithm to make sure the contrast of the text on the background is high enough.

If you are using Gmail and choose not to receive your email in mail.app using POP, chances are you are using the free Google Notifier (formerly Gmail Notifier). This is a menu bar item that alerts you when new mail arrives and in its latest version, adds Google Calendar functionality.

One of the greatest benefits of this piece of software is its simplicity - just put in your Google ID and password and everything works. At times this makes the notifier look somewhat limited, however this couldn't be further from the truth.

The first hidden feature is to customise the number of messages shown in the notifier menu. By default, the menu shows the last four unread messages received (or the last three received and an additional "View More" submenu). To change this, pull down the notifier menu and hold Command and Option while clicking on preferences. This brings up a hidden settings editor where you can easily edit the notifier preferences file.

In the "Key" field, enter "MaxMessagesOnMainMenu" and in the "Value" field enter the number of messages you want on the main menu. Click Set, and then quit and reload Google Notifier. Now when you click on the notifier menu bar item, you will see the number of messages that you set. To return to the default setting, repeat the prcoess, putting 4 in the value field instead of the number you entered last time.

The second trick can be done in much the same way. If you only want the notifier to fetch mail with a certain label, you can create a filter. As before, click on the notifier menu and Command-Option-Click on preferences. This time, in the key field enter "Label" and in the value field enter the name of the label you want to receive. To receive all mail, leave this field blank. And again as before, quit and reload the notifier for changes to take effect.

When you set these preferences, you are actually editing Google Notifier's preference file (Library/Preferences/com.google.GmailNotifier). If you want, you can load up this file with Property List Editor or TextEdit and changes things yourself (be careful!) or you can achieve the same effect using the Terminal (Applications/Utilities). For example the previous trick could be done by typing the following into the Terminal:

defaults write com.google.GmailNotifier Label -string “YOURLABELHERE”

Finally you can extend Google notifier using plugins. I found the following on the Official Google Blog:

The Gmail Notifier supports plugins written in AppleScript, or full-blown Cocoa Bundles in Objective-C. Details about the Objective-C plugin API can be found inside the Gmail Notifier application bundle in the required header file, GGPluginProtocol.h (control+click Gmail Notifier.app -> Show Package Contents -> Contents -> Headers).

AppleScript plugins are written by simply implementing a handler like:

on NewMessagesReceived(messages, fullCount)
-- Your code goes here...
end NewMessagesReceived

To install, simply copy the script (plugin) to Library/Application Support/Gmail Notifier (create the directory if it doesn't exist), and restart the Gmail Notifier. An example of a great plugin for the Gmail Notifier for MacOS X is the Gmail+Growl plugin, which sends Growl notifications when new mail arrives.

When you start up your mac and the login window pops up, you have a big shiny apple logo and the words Mac OS X. Below these words you usually see the name of your mac, whatever that may be. For most people that isn't very useful, as you have to have a lot of the same models knocking around to get confused between computers, and luckily since Mac OS X 10.4.3, this line has been made much more informative.

Since this version, you can click on the name of your mac to show different statistics about your machine. Each time you click, it will cycle through different bits of information that are particularly useful when troubleshooting problems.

The order of the statistics are as follows:

One click: Your OS X version number (e.g. Version 10.4.7)
Two clicks: Your OS X build number (e.g. Build 7M271)
Three clicks: Your mac's serial number (e.g. WN1511LHKNW)
Four clicks: Your mac's IP address (e.g. 196.254.0.1)
Five clicks: The status of any networked account
Six clicks: The date and time (e.g. Saturday, January 20 2007 4:02:31 AM GMT)
Seven clicks: Back to where you started, the name of your computer.

So you click a few times and set the information line to your favourite thing, but next time you log in, it has changed back to the name of your mac. To change the bit of information that appears first, you need to do a bit of tinkering in the Terminal (Applications/Utilities). Open Terminal and type the following command:

defaults write /Library/Preferences/com.apple.loginwindow AdminHostInfo info_name

Depending on which piece of information you want displayed, replace info_name with one of the following:

SystemVersion
SystemBuild
SerialNumber
IPAddress
DSStatus
Time

After doing this, hit return, and the next time you view your login window the information you chose will be displayed.

In OS X it is easy to create as many user accounts as you need. It's definitely useful being able to have an account for each family member, or an account just for troubleshooting. However, this also leads to an extremely long list on the login window, and an annoying scroll bar down the side.

If you are running Tiger, hiding user accounts that you rarely use is simple. Firstly, go to the Accounts pane in System Preferences, and find the "short name" of each user you want to hide. Once you have these, open up Terminal (Applications/Utilities) and enter the following:

sudo defaults write /Library/Preferences/com.apple.loginwindow HiddenUsersList -array-add shortname1 shortname2 shortname3

Obviously shortname1 2 and 3 will be replaced with the short names of the user accounts you wish to hide. You can hide as many as you like, just separate each with a space.

To make a hidden name appear again, type the command with no names in it, therefore resetting the list of hidden users.

sudo defaults write /Library/Preferences/com.apple.loginwindow HiddenUsersList -array-add

Notice that doing this adds an extra option to your login window - "Other..." When you select this, you will be presented with text boxes to enter a username and password.

If you aren't running OS X 10.4, another option is to completely get rid of this list of users. Go to the Accounts pane in System Preferences, and click on Login Options. There you will find an option to display the login window as name and password fields. This isn't as pretty, but saves time if you have lots of users, and is also more secure.

Here's a quick fun tip that I found over at macresearch.org.

• Make sure you have a cool screen saver set (macresearch suggests the RSS visualizer)
• Open Terminal (found in Applications/Utilities)
• Type the following:
  /System/Library/Frameworks/ScreenSaver.framework/Resources/
ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -background
• Look at your Desktop.
• To stop the whole thing and return your desktop to normal press Control-C (or Command-.)

There are a few things to look out for with this: Depending on which screen saver you are running and what mac you are running it on, this make take up a large CPU load. Also, your normal background will be shown when pressing F9 or F10 to activate exposé. Finally, if your screen saver starts (from a hot corner or by inactivity for a certain time) it will cancel the screen saver on your desktop.

These hidden files are accessable from any unix based operating system, including linux and Mac OS X. To see a list of what there is to offer type -

ls /usr/share/emacs/21.2/lisp/play
into a terminal window (terminal is located in Applications/Utilities)

To play the games, open a new terminal window and type “emacs” and hit return. Once in emacs, press Esc then x to get to the prompt. Now you can type any of the files in the list to play them.

My favourites are:
snake, tetris and pong, the old classics.
doctor, a shrink in your mac (he/she isnt that helpful, unless you threaten to commit suicide)
life, one of the first screen savers.
dunnet, an old text based game where you can explore
zone, makes the text on your screen go crazy

Have fun!