Time reports: "Few Americans realize that their cars can tattle on them. But among those in the know--civil libertarians, law enforcement agents and consumer advocates--a debate is surging over the black boxes technically called event-data recorders (EDRs). While some welcome them as a safety measure, others fear them as an Orwellian intrusion. Nearly one-third of vehicles on the road today--and 64% of this year's models--contain the little-noticed chips and sensors. Unlike flight recorders on airplanes, these microcomputers don't capture voices, but they can retain up to 20 seconds of data on speed, braking and acceleration in the lead-up to a crash. For virtually all Ford and General Motors cars, and for a few models from other automakers, accident investigators can buy a modem-like device to plug laptops into EDRs and download the information."
I read about this technology a few years back, but it now seems that it's going main stream. The technology was designed as a blackbox type of device for monitoring what happens in a crash just before the airbags were deployed. These devices have been used as evidence in several cases involving crashes to prove innocence and guilt.