My balls (I love saying that!) like cardboard boxes as hides. Fuzzy, our bigger bp, likes to lay on top of his, crushing them. It's not like they are too big for him, he's just ...rude like that. We use soda boxes, cut to shape and size. He can crush them all he wants, he'll lay on top of them for a few hours then I suppose when it is sufficiently modified, he'll attempt to crawl back in and end up looking like a turtle with a box on his back moving around his tub. Strange little animals...