Traffic safety would be greatly improved by a system whereby cars could automatically communicate their speed, rate of acceleration / deceleration etc. to each other. Has anyone considered using brake and parking lights as a way of doing this? I could imagine that by rapidly flipping on / off some of the LEDs, it would be possible to communicate simple information to following vehicles with capability to read the signal, while to other vehicles without such capability they would flicker so fast as to just look like normal brake lights.