Streetpong adds a small touchscreen to the buttons usually used to trigger traffic lights to change. When someone presses it, a game of Pong starts up. But to make the idea really cool, if there's a person on the other end of the intersection, then the two people play against each other until it's safe to cross the road.
German students in a design course first developed the basic idea in 2012. They put out a video showing how the concept would work and started a company to make it a reality. Just recently, there was a grand unveiling of the system actually running in the city of Hildesheim, Germany.