Comment Against the Fall of Night (Score 1) 333
In Arthur C. Clarke's Against the Fall of Night there was a city wide transit system that operated like this, only it could move each person at a different speed by being able to control arbitrary areas of the walkway, and move them through the surrounding surface. An explanation involving materials that could be translated between different dimensions was given, if I recall correctly.
*encourages scientists to develop such things*
*encourages scientists to develop such things*