for those of you who don't know, check out the site:
http://folding.stanford.edu/
here is the Wikipedia description because I'm too lazy to describe it myself:
Folding@home (sometimes abbreviated as FAH or F@h) is a distributed computing (DC) project designed to perform computationally intensive simulations of protein folding and other molecular dynamics (MD), and to improve on the methods available to do so. It was launched on October 1, 2000, and is currently managed by the Pande Group, within Stanford University's chemistry department, under the supervision of Professor Vijay Pande.
Folding@home is the most powerful distributed computing cluster in the world, according to Guinness,[1] and one of the world's largest distributed computing projects.[2] The goal of the project is "to understand protein folding, misfolding, and related diseases."
every PS3 has an integrated folding@home program that you can download through the playstation network. one work cycle takes about 6-8 hours, so i just leave it running over night.
I also run it off my gaming rig when I'm not away at school.