We aren't there yet.
Oh yes we are! Take a look at some of the latest BMW and Mercedes models, especially the ones with electric power steering - some have available options such as "active lane keeping assist" (each manufacturer names it differently) which can automatically "steer" the car if it starts to "drift" out of its lane, or "active parking assist" which basically steers your car into parking spot semi-automatically, or systems which automatically brake the car if they sense an imminent collision. All of these are controlled from single ECU and some of these features are available (as an option) even on cheapest models (like the new BMW 3-series).
Of course you can't control or hack these systems from any wireless device yet (the current Mercedes Mbrace or BMW Assist systems are incapable of sending the commands to car's steering/throttle/brake subsystems) but if the car manufacturers will continue to blindly add in more automation systems - it may be a very near possibility.
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