1: It has to exist, we _can't_ be alone in the galaxy.
Dunno when we'll discover it, but it'll definately be by the help of SETI@home and such things.
2: Yea, sure. Beacons are cool. What information we should send? I don't think it'll matter because I don't think those who are receiving it will be able to understand it anyhow.
3: My computer is on 24/7 and since I'm online 24/7 aswell I might aswell run something so that maybe I'll make a difference somehow.
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.