Papercraft heart made out of working gears by Haruki Nakamura. You can see it in action in this video (it gets cranked up starting 50 seconds in):
As far as I could tell, the template is not available for download. But I did find this globe puzzle by Nakamura.
You can download it here. Via.
*You can download dozens of easy papercraft projects here.
*Buy heart pendants at Amazon.