"S" plates for "Senior" drivers
My Dad is a senior (over 80) and he still drives. He would be happy for people in front or behind to know that he is older than most by displaying an "S" plate, which lets other drivers know that he is over 80. I think it's a great idea of his because it will inform others that there is a reason why he might be going a bit slower and to be patient. If we are lucky to live that long we'll all be in the same boat. We have "L" plates for learners, "P" plates for probationers and we should have "S" plates for seniors.