[fibber2]

Let's just assume that the whole game was in the mirror. Per one of the parts sites, replacement units are over $500 a piece. Now they have to be integrated in to the system, so you'll need some programming support. For instance, they flash when you turn on your directional, so they receive a signal from the body control unit (another microprocessor). So unfortunately it's not so easy on a newer car to add features.