I run SETI@home because it makes me feel like I'm part of something bigger than any one person. It's something that could possibly benefit everyone one day. It could also bring our ruin to us. It's a gamble either way and it makes the idea of extraterrestial life, which does exist, that much more interesting.
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.