We were talking about Seti@Home in my Linux class today so I decided to give it a go with some spare CPU cycles I have.  I was just gonna use my Win2k desktop here until Kevin informed me that there was a Linux client as well.  It's not open source, but I won't complain too much.  Regardless...  I now have Seti@Home running on 5 machines for a combined 4770mhz of Seti@Home processing power!