Predator Free Edition
If you leave your PC unattended and running in a public area, how do you keep people from using it? You have several options, but one of the easiest we've tried is Predator Free. This free security tool locks and unlocks your PC when you remove or insert a USB drive. When your thumbdrive is removed, Predator locks your PC and darkens your screen if anyone tried to use it without entering the password. You can enable passwords for every operation or just once, which adds convenience if you're often away from your desk. It also logs activity and can sound an optional alarm. If you lose your USB drive or don't have it handy, you can still unlock your PC with your password.
Click here to download Predator