The P2P network giant, Sharman Networks, has finally revealed an ulterior motive behind their P2P software. KaZaA has been equipped with a Trojan known as Altnet, which will steal your ?spare processing, storage and communications power?.
Designed by BDE, Altnet has been part of KaZaA since March, and has been downloaded by millions of users without their knowledge.

Full KaZaA: Spyware Not Enough - Now It Comes With Trojan story.