As more and more small white dots are added to this black-and-white checkerboard in arrow patterns, your eyes are automatically drawn towards its centre, and you'll start to start to think it looks warped. But it's not. Excuse me while I go vomit.
All those connect-the-dot puzzles I did as a kid must have done more harm than good. I can't even imagine the havoc that colouring inside the lines has wreaked on my psyche. [YouTube]