Let your Laptop scream if it is being stolen, with Mobile SafePatrol
Mobile SafePatrol is a free (for personal use) program that will help protect your laptop by sounding an alarm when your computer power cord is unplugged, when your laptop lid is closing, when your computer battery level is low.
Easy to Use * Lock your computer to prevent unauthorised access * When your computer is locked:
1) Ctrl-Alt-Del combination is blocked, 2) Booting into “Safe Mode” is disabled, 3) Switching into another user account is not possible.
The program is not under active development anymore, but you can try and see if it still works.