> Waiting for the light to change is a huge waste of time for both pedestrians and drivers

That's because it's designed and run by the government, which has no interest in saving time.

How many hours do we all waste waiting for a light to change when there's no cross traffic? having a "platoon" of cars come to a halt to let one car cross? having a light turn yellow at the last moment to slam on the brakes? How much gas has this cost, too?

By mounting cameras on the lights and a little AI programming, and an optimization algorithm, I bet the lights could be a major factor in reducing gas consumption, smoothing traffic flow, reducing accidents, and saving time.

In fact, the AI could be self-learning, like the fuel injection systems on cars.