I stumbled on an interesting article over at ComputerWorld. Adware companies are now flooding P2P networks with fake mp3 files.

…McAfee Inc. reported that it has seen a huge spike in fake MP3 files spreading on peer-to-peer networks. Although the files have names that make them look like audio recordings, they’re really Trojan horse programs that try to install a shoddy media player and adware on your computer…

See link for the full article:
http://tinyurl.com/4ycqdo