V2V

You're driving through town with your mind half on work, half on the traffic around you. You come to the two-way intersection you've crossed a thousand times before, stop, look around and start to turn left.

And then your car sounds a warning bell, loudly and insistently. It's telling you, "WAIT -- the pickup truck barreling straight at you can't stop in time."

Got your attention, no?

It works because your car and that pickup are exchanging their location, speed, acceleration, direction and steering faster than we can blink. Many consider this conversation -- called vehicle-to-vehicle, or V2V -- the most important lifesaving technology to hit the auto industry in the past 10 years.

If V2V did nothing more than warn you not to turn left or enter an intersection, it could prevent about half a million crashes and save around 1,100 lives a year, according to the National Highway Traffic Safety Administration.