I was flipping through the channels yesterday, and I found an old episode of MAD TV on TNN. I turned it on right in the middle of this sketch where there was two men and a woman on stage(sorry, I don't know names) they were dressed as little kids, and the two men were attempting to make the woman smile. She refused to smile until they both started tickling her face(WHAT? her face?). She then lets out a huge smile and laughs saying, "Hey! That's a tickle smile!"