Raymond Chen recently had an interesting blog post on the importance on checking your monitor's refresh rate to reduce eye fatigue. One of the comments posted pointed to the Windows XP ClearType Tuner page that will walk you through the process of setting the optimal ClearType settings for your system (thanks Jerome!).
UPDATE (1/27/05):
Microsoft has released a ClearType Tuner PowerToy that you can install and run as a client application. Very cool!
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