Vuwer - It's lojack for your Laptop Except Vuwer is Free
Vuwer works much like the lojack software for laptops except Vuwer is free and doesn’t cost anything. Vuewer pronounced “Viewer” is a service application that runs in the background. If your laptop were to get stolen you could capture the IP address of the computer, which the police could use to track the address of the computer. You can also use the built in isight camera to take a picture of the criminal or at least whoever has your laptop currently. You can also take screen shots of the screen to see if that would help discover the identity of the criminal.
This application is not as easy to setup as the one lojack offers but this program is 100% free and there is no signup or service you have to pay for. Of course it doesn’t have guarantees that the other similar software’s have but once again this one is free. I think this is a great little precaution that can be taken just incase your computer is ever taken.
Vuwer Homepage - Contains directions on how the application works and how to install it.