This is one of my favorite drawings for home- or lock-screen on iPad. I think I got it from the app Pimp My Screen, though sadly I don't think there are many of the type.
I just think it's lovely. For one thing, it's cunningly made so it fits nicely on the iPad screen regardless of screen orientation. For another thing, it's a nice drawing and has great, warm colors, and the idea is just so dahlink.
BTW, tip from podcast iPad Today: to put a message on your lock-screen (like where to call if somebody finds it), just write text on a graphic! It can even be done as simply as writing on a note app and taking a screenshot (homebutton plus sleep button simultaneously). Then select it for lock-screen.