Everyone can appreciate a good optical illusion. Wait, scratch that: everyone can appreciate a good optical illusion that's decipherable — not one of those inscrutable, impossible-to-figure-out illusions from hell.
With that out of the way, who wants to see some fun illusions? These might not all technically be optical illusions, and yes, some of them might be a bit baffling. But all in all, they should give your brain a little workout.