If you don't the default blue outer-glow in Exposé you can easily hack to make it look more appealing.
Go to the folder System/Libary/CoreServices. Locate the Dock application. Ctrl-Click it and select Show Package Contents. Within that navigate to the Contents/Resources folder. Here you will find two png files: expose-window-selection-small.png and expose-window-selection-big.png You can overwrite these to create a new look.
Sorry to pitch another Google service, but this is a really useful tool. :) Google Browser Size shows you how much of your website people see without scrolling. This can be important to make sure important elements of your site, like navigation are visible to as many people as possible. Also it gives you a good idea about the number of people who will see your extra wide website layout in its entirety.
By default most of us use our ISP's DNS to resolve web addresses into IP numbers. Google came up with a Public DNS system, which is is supposedly faster (and perhaps safer) than using the ISP's DNS. If you want to test it on your Mac it's really easy to set it up.
If you want to help a friend to fix a Mac or want to buy a used Apple machine you will need detailed and extensive information about the computer. The easiest and fastest way to create a document that can be emailed is to export a text document with all the details from System Profiler. Here are detailed instructions:
Open Applications/Utilities/System Profiler application