Windows XP PowerToys - ClearType Tuner
ClearType manages and enhances font smoothing, to make letters and numbers appear crisper and more distinct, particularly on notebook computers and flat-panel LCD monitors.
Your computer screen can cause significant eyestrain if it is not adjusted properly. This free Microsoft PowerToy lets you use ClearType technology to make it easier to read text on your screen, and installs in the Control Panel for easy access.