Found this today while doing research at work. Apparently this veterinary trade magazine, Veterinary Practice News, has a contest called "They ate WHAT?!". Contestants are invited to submit x-rays. This year's winner: A Burmese Python "that had not only consumed its dinner, a rabbit, but the electric blanket underneath the bunny."
The student prize winner was a dog that ate a stuffed dog. The (real) dog apparently has a "history of eating socks".
Check out the slide show of runner-ups.