It's probably unfeasible, but it would brilliant to have a "report file" system, when the client reports the file as junk, it's checked out, and if found to be junk, the hash is automaticly downloaded to all limewire clients to be used as part of their junk filter.. you could even (server side) store the file as it's hash which would easily allow you to check/disguard multiple reports of the same file..

may take a bit of time at first, but I'm sure after a while it would also act as a deterent to potential spammers.

But like I said, a lot of work.

Ed