WCG

I have no idea if the World Community Grid’s efforts will lead to a cure for AIDS (or anything else), but they’re currently doing a project on it and I figure it was worth mentioning. You can read exactly what they’re doing for HIV here.

Basically, you install a program that uses your computer's idle processing time to work on chunks of very large problems. It would normally take thousands of years for one computer to do the work, but since there are thousands of users it gets cut down to a matter of months. Right now, the collective effort amounts to around 180 years of processing per day.

If you have a computer with Internet access (or an office full of them) I would urge you to consider installing the software. You shouldn’t even notice it once it’s running.