Another submitter sent in a related submission about the collision data recorders in many late-model cars - which serve a similar purpose as the black boxes described above, but generally only record the last five seconds before an accident.
geemon writes "With the recent stories of rental car companies using GPS to track how and where their patrons are using their vehicles, this information about autos from 1996 and newer having an airplane-like accident "black box" capability was a complete surprise. Tucked under the drivers seat of most GM vehicles, the "black box" can store a variety of info such as vehicle and engine speed, braking, and seat belt usage. Info from an accident reconstruction service that uses this data can be found here. Called "event data recorders", these devices were, "...Originally designed to improve air bag performance based on the severity of the collision, the event data recorder can tell traffic accident investigators about the car's speed; engine RPMs; how far the accelerator pedal was pressed; if the brakes were applied; whether the drivers seatbelt was buckled and what warning lights were on - all from five seconds before impact..." It seems that GM and perhaps Ford have been using this for some time. Here is one company that makes the Windows based retrieval hardware/software combo for $2500. Imagine the uses of this data that law enforcement, your insurance company, and lawyers may have after your next little mishap."