I've seen this little guy in House Beautiful and on Apartment Therapy and it makes me wish I had a door that needs stopping. Meet Stoppy:
Is he cute or what? According to the maker's web site, Stoppy comes in ALL SORTS of colors, but I can only find a few on Amazon.com. (Home Depot and Target only carry the black, and OranizeIt.com has it in black and white)
A great stocking stuffer at $7.99.