I've been a SETI@home supporter almost from day one.
The search for extraterrestrial life that didn't originate on earth is of great importance for humankind as it would answer a fundamental question: are we alone in the universe? Maybe we are alone but that would be quite a waste of space. The thought that the universe is bristling with life in abundance is much more satisfying.
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.