"Sam Loyd's 'Trick Donkeys'
is one of the most elegant puzzles ever invented... print out the page and cut the figure into three parts along the solid lines. Now, position the strip onto the other two pieces so that it looks like each jockey is riding a donkey. Folding is not allowed. Don't give up -- the solution is really quite simple!"
Stolen from Metafilter
. It's pretty crafty. Took me like 10 minutes to figure the stupid thing out. My coworker figured it out apparently while cutting it out.