It seems that the state of South Carolina - rarely at the forefront of anything - may be proposing something fairly interesting: An electronic license plate.
There is no telling if these plates would ever see the light of day. For one, they are potentially expensive - the inventor is trying to get the cost under $100 per plate (which means that they are over that point now). There does not appear to be a reliable source for the cost of the metal plates, but since they are often rumored to be stamped out in stacks by prisoners, you have to assume they are awfully cheap.
Which makes the question: Why switch?