Designer: Jen Troyer

3 of 16
Cats have no trouble making humans laugh—by now, Tom and Jerry, Lolcats.com and the most extreme sourpuss of them all, Grumpy Cat, have made that abundantly clear. But how often do humans return the favor? Rarely, judging from an expression from the American South, "Enough to make a cat laugh." It's not known what it was that provoked such whiskered mirth, but it must have been hilarious indeed.