Here is a wonderful and complex paper automaton kit designed by the talented PaperPino. This one is entitled Wandering in the Sky.
From the automaton's description:
The three-gear train moves the wheels of the tricycle, and the scotch yoke mechanism moves the bird wings. Connected to the pedals, the clown's legs are linked with a lever system that moves the right arm and the head. With the Removable Inter-locking Pin System (RIPS), most of the parts are assembled without glue.
Want more on paper automata? Here's an older post with a round-up of paper automata resources!