Honestly, I don't think extraterrestrial life exists. Life is too complicated. It's a miracle some life was created at all. But I run seti@home anyway. I wont reject the possibility. And maybe we'll find something else interesting?
And of course: what else should my computer do? Word processing and compiling don't actually require one giga hertz. I get a little less embaressed of having this powerful computer when running seti@home.
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.