Much like the smartphone tracker, I love Sprite Terminator. Not free, it will set you back $14.95, but it gives you the ability to remotely lock the device, view call history for the last 10 calls, location, and the ability to perform a hard reset if you have sensitive information on your phone. Plus, I like to screw with my wife and lock her phone remotely!
Edit:
http://www.spritesoftware.com/produc...ite-terminator