My Dad is a big fan of Timberkits wooden automata kits and has built most of the range, or at least has received them as presents and will get around to building them one day.
His latest, and my favourite, is this wooden biplane. Wind the handle and the aircraft swings around the skies with it's propeller turning and the pilot giving everyone a thumbs up from the cockpit.
The ingenuity of the mechanism is astonishing. Not only have the designers made something that works (OK, the belts driving the prop have stretched a bit and slip) but can be assembled by normal human beings and not engineers. There's a lot more work behind the scenes than I suspect we think. All this has to be cut, packed and stuck in a box for under £27. Not bad for the entertainment they provide.