Let's get scared:
Researchers at UCSD have modified an MP3 file so that when it is played on a car's stereo system it modifies the stereo's firmware and opens up a security back door into the car's operating system. Using it, they were then able to control the door locks, the car ignition, and change the speedometer reading.
They hypothesize that black-hats could create such modified files and spread them around on the torrent networks. And given that some cars now are networked and contain GPS systems, they say that cars which become compromised could be programmed to announce their location so that thieves could locate and steal them.
Swiped from Chocolate Pickle on Metafilter.