This is something that might better fit in the Distributed Computing folder, but it doesn't seem to get much traffic.
Folding@Home is a distributed computing project that focuses on finding a cure for diseases like Ahlzheimers and Parkinsons by analyzing how protein molecules fold. More information can be found here:
http://folding.stanford.edu
Its a great project, a worthwhile one, and really something you can donate CPU cycles to. It can be configured to run as a service, (meaning completely invisibly) as a console client, or as a graphical interface.
Here's the part where I'll admit to being a bit selfish, heh. I'm hoping to find some people who'll fold for me and help boost my count. Failing that, I'd like to find some people who're willing to fold for my team (10688 is the team number, Sudhian Media is the name).
But failing both of those, I'd still like to find some people willing to contribute CPU cycles to a worthy cause. I've lost two grandparents two ahlzheimers and an uncle has Parkinsons, so I admit these are diseases that've affected my life personally.
Anyway, I'd be glad to help people set it up to run any way you like. Folding will NOT slow your machine in any way (Tech-Report.com has done formal bench-testing to prove it) and its a great thing to donate a little time to. And if people want to start their own team, hey, that's still great.
hardware
prices 
