Sure, pedestrian detection tech for cars is already in the works, but the city of London wants to keep people even safer by equipping its crossings with a bunch of sensors and devices. London Mayor Boris Johnson just announced that the city will try out a smart crossing system, which he claims has never been tested anywhere in the world before. It uses cameras mounted on traffic lights to detect if pedestrians are piling up, and it automatically adjusts signals to give large crowds longer time to cross the road. In the future, the reverse might also be true: the city's transportation agency plans to tweak it so that lights change more quickly when everyone's safely on the other side.