Finally, it will mimic a hardware problem presumably prompting the thief to take it in for repair or sell it, in which case it will display a message indicating that the computer has been stolen, etc. Orbicule is apparently so confident that Undercover will allow you to recover your machine that they're offering a money-back guarantee for the cost of the software if you do not. They have an interesting account of the recovery process in an actual case.
Undercover is $49 ($39 for students; education site licenses are available).
[via Daring Fireball]