If your cat is going to play with every cardboard box that comes into the house, you might as well make one of them his house. The Krabhuis (Dutch for scratch house) was created with playful cats in mind. Designed by three Dutch architects, the environmentally (and kitty) friendly play house is made from 90% recycled material that consists of 48 layers of duofold cardboard. Translation: cats are going to love it. In turn, they will love you lots for keeping their hearts content all day long.