A pre-crash avoidance system whereby the car will recognize an upcoming object and automatically brake if the rate of speed is excessive going into that object, particularly given the distraction concern with the center display.
Several high end cars offer similar optional systems. For example, the Lexus LS460 offers a pre-collision system for $1500.
Already implemented, but for some ridiculous reason it won't stop the car and avoid a crash, it only reduces your speed by a set amount and then gives up, should continue to brake until the collision has happened, or is successfully avoided.
I've heard of a system that allows the cruise control to maintain distance on a car that it's following. Crash avoidance might be the same system? The main item to be sensing an excessive closure rate. Maintaining closure distance could easily be done with low power laser.