Mac Security Alarm System 243
RogueAce writes "A program named iAlertU sounds a screeching siren when someone attempts to steal your Macbook. Thanks to the sudden motion drop sensors that Macs use to park the hard drive, iAlertU can detect when your Macbook is being picked up, moved or closed. Also, by using the handy remote that comes with the Macbook, you can turn the alarm on and off like you would a car, which the Macbook responds to by making the all too familiar chirping sound and a flash and flicker of the screen. The code behind it is from a guy named Christian Kleins."