You can find Linux clients for several file-sharing networks. Taking into account how many clients are available for each, the current top three peer-to-peer (P2P) networks are eDonkey2000, FastTrack (derived from Kazaa), and Gnutella. Here are some desktop applications that allow you to become a full-fledged file sharer.

And yes there are legal reasons to use P2P folks, Baldy
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