I'd love a tarrasque, just for geeky value. None of the icons are all that useful in standard RPG, as its a bad scale to represent a fight with them. The colossal red covers over 6 FEET of map per round. Something like a battletech scale would be more useful in a combat against one of those beasts, unless its fatly sitting in one spot (not likely in my games).
Corpse Tearer would be great as well... a nasty dragon with atrophied legs, moss growing out of it, etc.