1) Yes I believe extraterrestrial life exists since it would explain the behavior of some of my friends. As for when we will discover it, just ask Cleo the Psychic. The benefits of this discovery would be the sharing of technology and the only danger that I can think of is that we get annihilated.
2) Should humans transmit a beacon for other to find? I thought we are already transmitting radio and TV shows so right now the aliens are probably listening to Marilyn Manson and watching re-runs of X-files. What information should we send? Marilyn Manson's latest CD and the best of X-files.
3) I run seti because I just built this computer and I want to see what this thing can do.
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.
