SoulSeek
From AMule Project FAQ
SoulSeek is an ad-free, spyware-free, just plain free (as in beer) file-sharing application.
It's only supporting Windows (32 bits) platforms and it's protocol and source code are closed.
NOTE: aMule is a separate project and is not related to SoulSeek in any way. More over, aMule does not support the SoulSeek protocol.
