CPU Filter: You know what they say about idle hands... What about idle FLOPs? Distributed computing (a.k.a. grid computing / a.k.a. cloud computing) has come a long way in the past years, and most people probably don't know the vast number of projects they can put their idle CPUs to work on - it's not just aliens and genomes anymore. There are more than one hundred projects ranging from 3D rendering to climate prediction to saving the world with nutritious rice to neurons and nanobots. Why not lend an idle hand?
You've helped crack mathematical games, you've searched for aliens, the cure for cancer, cure for AIDS and even tried to calculate pi. What's left to do in distributed computing? How about helping the fight against anthrax? Remember, if you don't download the screensaver, the terrorists have won.
Popular Power has released version 0.1.1 of its Worker software. It works kind of like SETI@home, except that the computing power can be organized to work on things like Influenza vaccine research, and they plan to compensate you for the cycles they use.