AutoPilot, years ago
Back in the age of saber tooth cats, Popular Science Magazine had an article about the new "super highways". Each lane was for different speeds, 70, 80, 90, 100 mph. Your vehicle was controlled by a device mounted beside the engine and picked up signals from a wire embedded in the road. You got to speed in one lane, moved to the next and so on until you traveled at the desired speed. The device maintained safe distance between vehicles, kept speed at the desired rate, and handled all driving needs such as steering and selecting radio stations as you traveled across country. You put in the destination you wanted to get off and you were eased into the slower traffic toward your exit point.
They didn't address the needs of the driver and passenger, such as restroom and dining stops, or the need to refuel the vehicle. I guess there would have been male/female "relief tubes" to handle the wet end of that problem.
A really good idea that didn't catch on. Since the advent of EVs, this would have been a good way to power the electric motors on long trips, with a chance to recharge along the way. Toll stations at the exits would bill for miles driven for the EV.