Of course :) It could be taken further I reckon with noise displacements etc. etc. but for more elaborate shapes to fit a cartoon approach I'd rather do that in Mud.
Snowfly: nice work. I was thinking of possible captions right away... "Say No! to rising Imax prices!" "All you need to fear is not fear itself, but KFC winning the fast food war!" etc...etc
sorry to let you down mate, but i couldn't for the life of me get rust to look believable like this without using photosource. Yes, there was a lot of tweeking in photoshop, but the rust is a result of around 5 - 10 photo sourced textures used as overlays and other various layer styles . . .etc. etc.