For those of you who may not have seen it, here's the online version of the article I wrote for MAKE Magazine a few years ago. The article shows you the steps I used to construct my surprise top hat. When a hidden brake lever is squeezed, a monster pops out of the top of the hat.
When I wrote the article, I used a rubber finger puppet. I have recently replaced this with a wooden monster of my design. The new monster has articulated arms which really adds to the sense that the creature is alive and actively pushing the top of the hat open. I gave him a surly look -- as if he is angered by his noisy neighbors. That would be you. Here is what the updated hat looks like:
Here is where you can see how I made the surprise top hat project, complete with materials list, step-by-step instructions, and photographs of the construction. Enjoy!