The Cat Cocoon is the invention of Warren Lieu, a Dallas designer who also created a dog "shelter" he calls The Leading Edge.
I discovered this ingenious postmodern replacement of ugly scratching posts (and, one would hope, hopefully scratched furniture) at Design Within Reach. But in doing some research to learn more about who designed it, I discovered a great online pet store, PostmodernPets, where they sell the cocoon for $50 less than DWR, making it a reasonable $250 (Bri, don't tell me that $250 is too much to spend to prevent future furniture destruction!). PostmodernPets offers the best dog beds I've seen, along with the cat Archipod, a totally funky cat house/scratching post designed by Elizabeth Paige Smith, who made the first cool feline furniture, the Kittypod. Compared to the price of the Kittypod and Archipod, the Cat Coccon is a bargain.