There's a cool article by Chris McAvoy in the January issue of the Linux Journal titled "How I Feed My Cats with Linux".
He's using an inexpensive controller, a serial port and a small Python program to feed his cats from the web.
There's also a post about the project on the weblog of the author.
Ok, now this definately qualifies as a hack, so I'm off to Crazy Hacks to add the project ;-)