1. yes ET exist, and will be found in then next 20 years, by pure luck.
2. advanceed technology, the danger is that human's will be slave's off an highly evoled race.
3. for the chance to find ET.
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.