Here's a scary story; Some Texas car dealerships installed 'black boxes' on cars they sold that would allow commands to be sent to the cars after they're purchased. The system is used to disable a car's ignitition system or trigger the horn to begin honking if the owner happens to forget to make a payment.
That's bad enough in my opinion, but it gets worse. A man laid off from the company that controls those boxes got revenge by hacking into the system and disabled or made the horns honk on dozens of cars. Here's what happened.