You probably already know about and use Napster, the big rage in MP3 sharing. Lately Napster has been involved legal battles with the music industry who is treatening to shut the Napster network down. Gnutella is a sharing community much like Napster, except you can trade any type of file, not just MP3s. And unlike Napster, there is no central server, so the government cannot shut it down. It is quite cool.
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