Man sleeping in the front of his car.

Get ready to marvel at the latest in auto technology: Cars that know when you're too tired to be behind the wheel.  Several car manufacturers are now offering models with safety features to prevent drowsy driving.

Mercedes has cars that will monitor how you normally drive, then flash a dashboard warning when you deviate from that norm.

Saab has also developed an onboard technology that actually monitors eye and head movements to detect signs of drowsiness.

Additionally, there's the Anti-Sleep Pilot, a soon-to-be-released removable dashboard device and iPhone app that will sense when you're becoming tired and have you tap a sensor in timed intervals to keep you alert.

So there are already cars that can parallel park themselves, and now cars that can keep you alert. Up next: autopilot automobiles, perhaps?

Tags: Breaking News

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