Well, I’m now up into the top 1% of users in terms of work units for SETI@home – rank is 46,744 out of 4.8 million users.
Why do I do it? I don’t really know – I used to run the distributed.net RC5 client but once the contest was over, figured I might as well use those spare CPU cycles to do something more interesting. If there is intelligent life out there, maybe they’ll have the answers to some of the more difficult problems we face or maybe they’ll just wipe us all out so we don’t have to worry about the problems of exhausting natural resources, polluting the environment and so on.