How smart is your car?

The $50,900 Mercedes-Benz E350 E-Class BlueTEC  sedan can pretty much take care of itself. It monitors its tire pressure, adapts its headlights according to the curve of the road, adjusts its suspension according to road conditions and even tells drivers when they get too drowsy to drive--all the while massaging the owner in "drive-dynamic" (they move when the driver does) multi-contoured seats.

But does all that fancy technology really make the E-Class safer to drive? Yes.

Take just one example: More than 30% of all drivers in the U.S. admit to having fallen asleep while driving, according to the National Highway Traffic Safety Administration. Sixty percent admit to driving while feeling drowsy. That adds up to roughly 100,000 crashes per year that can be blamed on fatigued drivers--71,000 people injured, 1,550 killed and more than $12 billion in insurance losses, NHTSA reports.

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Mercedes-Benz's attention-assist program works by creating a driver profile that uses braking, acceleration and road conditions to judge a driver's typical behavior on a given trip. When the system detects a significant deviation from the profile, it assumes the driver is drowsy and triggers warnings to that effect.

In short, the E-Class embodies what it means to be a smart car: to communicate well with itself, the road and other cars, plus anticipating and responding to the needs of the driver and passengers.

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