But it was worth it! Check out these optical illusions!
Who knew there was such a contest? Well, Gus did, actually.
I liked the first one, Filling in the Afterimage after the Image. It's kind of a visual version of the hot/cold water trick. (Put one hand in a bowl of hot water and the other in a bowl of ice water for about 15 seconds. Then, put them both in the same bowl of warm water.)