catfish said:
how much bandwidth does this use? I would be keen but I am capped at home.......
On the whole very little. A single SETI@Home workunit is currently a bit under 400K, and depending on your computer should last some number of hours. Anything at all recent and it will be well under 10. You can find programs like SETIGate which can cache as many workunits as you want at one time, though.
However, they're also working on a complete remake of the basic program, which can cache multiple units on its own. It's called BOINC, and is made to also support other shared processing efforts. However, since I started trying it out about a month ago they've had all sorts of server difficulties with this new one, so just stick with the old program for a while; they're doing the same work.