If you have an accident in one of the 2.5 million cars whose owners subscribe to General Motors' OnStar telematics system, air bag sensors and other collision detectors will trigger a wireless alert to OnStar's call center, where an employee can notify a 911 operator of your location. But in the next few years, far more data -- including information on the force and direction of impact and whether the car has rolled over -- will also be available. And this data will go not just to OnStar operators but directly to police and emergency room doctors, who can gauge the necessary emergency response and medical treatment even before the first squad car reaches the wreck.

OnStar is wrapping up tests of the turbo-charged telematics technology in Minnesota. As part of the tests, detailed crash information is being sent electronically to OnStar call centers, which relay it to 911 operators, to select hospitals, and to state police dispatchers. According to Brad Estochen, project manager with the Minnesota Department of Transportation, the goal is to expand the test system by the end of the year, so that the data travels in real time to a Web server accessible by all hospitals, local police agencies, and other emergency responders in the state.