At some point, everyone encounters a file that just won't delete. The most common situation is a file that sits in the trash and refuses to be deleted, however many times you restart your mac. Here are 4 different methods for removing stubborn files, at least one of which is guaranteed to work.

Method 1 - Secure Empty Trash
Probably the most simple solution, and almost always works. Go to the Finder Menu in the top left corner of the screen and choose "Secure Empty Trash" located right below the usual Empty Trash. Secure Empty Trash is normally used to make sure deleted items stay deleted by writing over them multiple times with random data. Luckily this option seems to be more effective with stubborn files than the regular Empty Trash.

Method 2 - Third Party Applications
There are many applications available that allow you to force the trash to empty. One that is completely dedicated to it is Super Empty Trash, a free application with the sole purpose of helping you empty your trash. There are a few alternatives that perform many other tasks as well, such as Mac Helpmate (free) and OnyX (also free).

Method 3 - Using the Terminal
This method requires a bit of care, as making a mistake in the Terminal can result in things going horribly wrong. To delete a file using this method, first open up the Terminal, located in the Applications/Utilities folder. Type in "rm -f " without the quotation marks, and with the space after the f. Then find the file that wont delete, and drag it to the Terminal window, and the path to that item should appear. Double check that this is the thing you want to delete, then press enter. If the item that won't delete is a folder rather than a file, type "rm -rf " instead.

If this still doesn't work, the next stage is to use "sudo rm -f " instead. This is a little more dangerous as you can accidentally delete lots more vital files. Carry out the steps as above, and this time you will be prompted to enter an administrator password.

Method 4 - Creating a temporary user account
This method is a little time consuming, but it is great if you don't want to use the Terminal. Start by going to the Accounts preference pane in the System Preferences and creating a new user account. It doesn't matter what details you give it, just remember the password. Next, move the troublesome file from your trash to the Shared folder, located in the Users folder. Log out of your account and log into the newly created one. From here, move the file into this users trash. Then log back out, and go back to your normal user account. Return to the Accounts pane in the System Preferences and delete the temporary account by selecting it from the list and hitting the delete key. Select Delete Immediately from the dialog box that appears, and the user account will gone, along with the stubborn file.

I recently did an interview over at cool-looking-stuff.com about myself and the Mac OS X Tips blog. Check it out if you are interested.

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.

This tip is really a general Mail tip that isn't specific to the Mac, but I'm sure many mac users have had the experience of their mail client chopping off the end of long URLs. When this happens, the person who received the message containing the URL can't click on it to go to the web page.

An easy way to avoid this is to put your URL in when sending it. When the person you are sending it to receives the email, the URL will still be nice and click-able.

We all have to admit that we are pretty lazy at times, and would love to make our computers do stuff automatically. And because we are lazy, we can't be bothered with stuff like Applescripts that are far too much effort to create. Here are a few tips to automate your Mac and make your life that little bit easier without going over the top with scripting.

The first thing to do is to make your Mac turn on by itself. You can set it to do this in the Energy Saver preference pane in System Preferences. Just load it up and click "schedule" and choose a time to start up (and/or shutdown) and on which days you want this. This will also wake up your Mac if it is asleep, but this might not work if you have a password enabled screensaver.

Instead of loading up the same web browser, email client and iTunes every time you start up your computer, you can set them as login items in the Accounts preference pane. Choose the login items tab, click the plus and select the applications you want to automatically start up. Popular ones are Mail or Entourage, Firefox or Safari and iCal.

As far a scheduling specific applications goes, you have to use applescripts or automator actions for most of them. If you aren't completely super lazy, it is pretty straightforward to create a workflow in automator that opens up a list of websites, or starts an iTunes playlist going. To get this worklow to be carried out at a certain time, create an event in iCal and set an alarm. As the alarm action, set it to open up the automator file.

However, in some applications you can get the same results without making workflows or scripts. For example, in Firefox you can set multiple websites as your homepage, and all of these will open up when you start Firefox. There are two ways to do this. The first is to create a folder of bookmarks with all the sites you want to load on startup. After creating this folder, go to the Firefox preferences and click "use bookmark" to select the folder. The alternative way is to type in each address into the homepage field with a | (pipe) in between. Be sure to set Firefox to load your homepage on startup using the dropdown menu.

Finally, some applications have built in scheduling capabilities. Microsoft Entourage has tools to set Send and receive schedules that check for email at certain times and Apple's Backup has its own scheduling feature to carry out automatic backups however frequently you want.

You can use all of these features to automate your Mac and make sure that you never have to carry out a tedious task again.

Here's a quick tip. Normally to make an application load at login, you have to open up System Preferences, go to Accounts and add a new login item. To quickly skip this stage out, right click on an application in your dock and choose "Open at Login". To undo this, just repeat the process.

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.