This is only a proof-of-concept script and could run in the XP, W/2003, and Vista environments.

MSH/Cibyz - Windows Powershell Proof-of-concept worm
http://vil.nai.com/vil/content/v_140292.htm

QUOTE: MSH/Cibyz!p2p is a proof of concept worm written in Windows Powershell script. It attempts to spread via the popular peer to peer application KaZaa by dropping a copy of itself in its shared folders. Windows Powershell is a command line shell and scripting language for Microsoft Windows that runs on Windows XP, Windows Server 2003, Windows Vista and Windows Longhorn.