This is just a collection of pictures I mostly found on the net (cracking contraptions screenshots are my own). I can't remember where exactly I got them all, but links to a few of the pages I borrowed from are in the links section.
Pictures from A Grand Day Out
Pictures from The Wrong Trousers
Pictures from A Close Shave
Pictures from Cracking Contraptions
Pictures from Curse of the Were-Rabbit
Pictures from A Matter of Loaf and Death Pictures from the Cracking Ideas exhibit