A user on the steorn forum just passed this along to us...
http://www.sandboxie.com/ (http://www.sandboxie.com/)
Basically its a safe point between your computer and harddrive, so anything malicious like malware, spyware and so on cannot get stored to the harddrive, anyway, just go to the link, they explain it better than me ;D
Oh I forgot to mention, it IS FREE and CLEAN.