Arthur Gugick of course. He's the guy who created this Batman/Joker lenticular, which when viewed from the right looks like Bats and when viewed from the not-so-right looks like.... well just hit play and see.
Yes, you can click and re-watch it again. Gotham knows I did. Now if he could just follow it up with a Flash/Reverse Flash version, I would be a happy, happy Dan.