We've already seen Audi show off a car-to-traffic light communication system, but the automaker has stepped things up considerably with a recent demonstration of its new Travolution system, which not only lets cars communicate with traffic lights, but other cars as well. The basic idea is the same as before: to cut down on pollution and fuel-consumption by reducing idling at stop lights and, in some cases, the need to stop at all. To do that, the system relies on a combination of WiFi and 3G, which currently lets Audi's 15 test cars communicate with some 150 traffic lights in Ingolsta
