If you use bittorrents, eDonkey, WinMX, Gnutella, Limewire,KaZaa, Direct Connect, iMesh, or any other network, then you are likely being scanned by investigators. In an effort to trap and prosecute people for abusing copyrighted movies and music, investigators often pose as P2P downloaders. Government agencies like FBI, CIA, riaa, the motion picture industry have dedicated IP addresses. From these addresses they have a bank of computers that constantly scanning and loging your IP (internet protocol) address. Your computer IP address then becomes ammunition for civil lawsuits, where you may be sued for copyright infringement.
PeerGuardian is a tiny IP blocker program especially designed for P2P software users, but also to anyone who is concerned about the investigations that corporations and authorities perform on the internet. PeerGurdian blocks connections for the configured IP ranges and logs the blocked connections. It uses blocklists for the blocking, but IP ranges can also be configured manually. Pre-cofigured for blocking are RIAA, MPAA and many others.
Important note: Peer Guardian is a filtering tool only, and does not replace having a security firewall to protect you against hackers