I run SETI@home because I think it is a noteable problem and the idea of using unused computers linked together to create a vast super-computer is great. This way of computing will be very valuable, if not for SETI then for some other computational problem.
The project seems valuable. I'm thinking we'll find life out there but I'm not certain it will be anything more than microbes. The Drake equation gives me reason to think that we are just one of many intelligent species out there. But even if we are alone, we are called to search and I hope we can enjoy the discoveries that are made.
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.