Kathy, that's a cool idea. I'm thinking about doing more "colorful" and less "naturalistic" ones next--will have to see what acrylics catch my eye next time I'm at the craft store.
Anyway, here's mine! Most the little ones I made (the muffin tin ones) ended up being too big for my needs (wee hatchling tubs!)... Oops! Oh well--they're just right for my yearling, and I'm Craigslisting the extra 6 to pay for more hide-making supplies.
The 8x8" one is going to be for my yearling boa (still a little-ish guy), just waiting for it to finish airing out.
And I'm not done yet-- I have a loaf pan sized one and about 15 or 16 even littler hatchling-sized ones in the works, and plans to make more. Between my older snakes and the roommate's corns and gecko... Well, let's just say I'm going to be VERY busy over the next week.
I'm even trying to devise a way to make one for under my beardie's basking spot, just need to find a big enough mold and find out whether it's safe to put slate tile in the oven... Hmmm!