What I think about SETI: It's the cheapest way to find out if we're alone or not. Barring our invention of FTL propulsion, it's going to be a while yet before we can meet face-to-face with other civilisations so this is the way to go. The fact that I can help in this endeavour is alot of fun.
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.