Run Windows XP and want to have the benefit of easier to read, less-jaggy fonts system-wide? Yeah, I thought so too. Right-click the desktop, select Properties, head over to the Appearance tab and click on the Effects button. In the window that opens up, check the second box that says Use the following method to smooth edges of screen fonts and select ClearType from the drop-down menu, then OK out of all windows.
Those steps will just enable ClearType on your system with the default settings. If you want to fine tune the appearance, download the ClearType Tuner from Microsoft and use its wizard. It can do things like adjust contrast and LCD screen striping.
After browsing around online on a friend's computer I realized how horrible everything looks, my site included, without ClearType enabled.