Nyan Cat, in an unreasonably huge size.
There are loads of Nyan Cats on Shapeways. This one has some minimal relief to it, but is mostly flat, while still being wide enough to stand on its own. The rainbow has been extended, allowing the front end to jut over edges, if desired. It's also been lowered enough so that the whole model sits flat. The two faces are identical, so you can make it face either direction.