take a look at this thread:
http://www.ball-pythons.net/forums/s...ighlight=hides

it shows the plant saucer, a tupperware, and some of the black plastic 'creature cubbyhole' commercial hides.
When choosing a size just remember that they like a snug fit, and the light plastic hides they eventually end up wearing on top of them like a hat but they still like it!