AICSM is a bit of a cheat really, alumnus of imperial college school of medicine. More letters I guess, but we're apparently legitimately allowed to put it after our name.
dowie: if there is an announcement on a plane asking if there is a doctor onboard, I think it would take a lot of balls for a PhD in physics to stand up. I don't want to get into an argument about medics being called doctors (i'm biased), you're technically correct. People do get confused when they see surgeons and have to call them Mr. somethimes.