Shantanu Goel created a cool home security tool using Twitter and a linux application called Motion, a program that will monitor a webcam looking for differences between frames.
When Motion detects movement, it archives a photo of the event and has the option of triggering an external script. Shantanu combined this with a simple curl command that will ping your Twitter account when a motion event occurs. The end result is a tweet that tells you that motion was detected and checking Motion’s integrated mini-http server will allow you to see if it’s a false alarm or view the intrusion in real time.
I’m going to set this up at work so I can track down who keeps running off with my red stapler.