Nah Gary......looked at all of those in December 06 when I was waiting for delivery mate.
P100 BHP, etc. There is another thread about 100HP plates elsewhere. Did see ones similar to the one you mention; 'P10 OHP' for example, but the repositioning of letters is illegal you know.....and a bit 'tacky' in my opinion. (Sorry if I've offended anyone on here who has - hope you've got a set of legal plates in the boot in case you get pulled by the Feds.)
But eventally decided that the car already has a '100hp' badge on the back and couldn't see the need for another.
Saying that my GTV has 'H** GTV'. So I've already done the car specific plate thing.
For the Panda I decided to get a plate that relates to the name of my architectural practice so that I can carry it on to other cars. And I think a short reg number suits a small car better than a 'maths formula' stuck on the back and front.