Like the system proposed by SkyTran or the discussions found at OpenPRT.
Basically, the idea is for a system of suspended tracks over most roads which allow for something much like 'overhead rail', but each rail car is only meant to hold one or two people. It doesn't have stops, it just goes to the destination you want it to. Because the tracks are computer controlled, it can be fast - over 80 mph without stops. It'll power the cars electrically, through the track, and because they're smaller/lighter than regular cars, it has an amazing energy equivalent of miles per gallon.
It's a lot like cars are today in terms of convenience and personal space, but smaller, faster, fully electric, and completely computer controlled with no chance of accidents or road hazards. It would be more comfortable and faster than any currently existing rapid transit option.
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