Limeware is not technically malware by itself, but it can install malware because it opens the door for any number of infections. In addition, the courts have decided that current P2P networks are primarily used to trade pirated software and media.
Some reading:
http://www3.ca.com/securityadvisor/pest/pest.aspx?id=453088059
http://www.benedelman.org/spyware/p2p/
a moderator on this site (Proffitt) mentioned that limewire is a "vile crock of...problems" how so? what are the risks and problems associated with it?

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