happiness hat from Lauren McCarthy on Vimeo.

The Happiness Hat that you will see in the video here will play with the Pavlovian principle when it comes to making you smile, where it will driving a metal spike into its wearer's head whenever it detects that the wearer is starting to frown. Not exactly the best method to induce a smile by any means, but it is no less effective, that's for sure. Sure beats getting killed by the Joker with a smile on your face, eh?