Are your cats old school gamers? If so, then they may enjoy If Industries's* cat scratcher design concepts. Its site has a wide variety of novel designs for household objects and clothing accessories. But these Atari and Nintendo controller scratching posts are obviously the coolest.
There is a functional Atari joystick much larger than this one. I don't see why it wouldn't be possible to wire up a combination joystick/scratching post.
-via Geekologie
*The noun is plural, but the object is singular. So, in accordance with Strunk & White, I've added an 's'. It's time for a poll!