Any cyclist will tell you that stopping at a red light is a drag. And when that light stays red because it needs the weight of a car to turn it green, it really puts a damper on your cardio workout. Most often lights that need to be triggered by cars are controlled by an inductive loop, a sensor embedded in the pavement that flips a switch on a computer to turn the light green. Cameras are increasing in number, but are subject to environmental conditions such as ran, twilight and wind.
Cycellicious reports that the city of Pleasonton, California is experimenting with the use of microwaves to trigger traffic lights to change. This method is more reliable than cameras, can distinguish vehicle types and give cyclists more time to get through the intersection than cars, and works with lightweight travelers such as cyclists. You may still have to wait at a few traffic lights, but the time will be reduced. About enough time to practice your track standing skills.