I am a gamer whose computer has a little too much time and more power than I need all of the time. I run SETI@Home so that I can help out a good cause and possibly have a chance at getting to see advanced technology. :) The project is in my opinion doing a novel thing by allowing the average joe to help with projects that would otherwise require massive amounts of processing power and data storage.
SETI@home and Astropulse are funded by grants from the National Science Foundation, NASA, and donations from SETI@home volunteers. AstroPulse is funded in part by the NSF through grant AST-0307956.