Seguro que a muchos de los que utilizais aplicaciones P2P, os interesará esto:
http://members.lycos.co.uk/linuxserv/peerguardian/index.htm
Peer Guardian is an experimental firewall program. Among other things it...

- Detects and closes connections from specified IP ranges.
- Blocks out known P2P enemy IP addreses by default.
- Allows you to manually close connections that have been opened by other programs.

PeerGuardian blocks connection on TCP/IP.
(KaZaA, Grokster, DC(++), Fileshare, etc. use TCP/IP)

PeerGuardian doesn't block connections on UDP.
(Blubster uses UDP)

The program was written after I'd seen many requests for something to universally block these companies out of file-sharing programs. A lot of people were asking where to get free firewall software, how to add the addresses to the firewalls block lists or how to add them in their specific P2P program. I'm not completely sure of it's effectiveness and that's why I'm releasing it as an alpha release. I can guarantee that PeerGuardian is safe and won't do anything bad but I'll have to wait for feedback before I can make any statement on it's effectiveness. It should work without problems for most people though.

PeerGuardian blocks out known IP ranges used by MediaForce, MediaDefender, BayTSP, Ranger, OverPeer, RIAA, MPAA & NetPD by default.

Recently added: Spyware IP blocking against GAIN & Xupiter.com

TseTse