I had thought you were talking about a paper background, like the rolls they have for fish tanks. For a cool background, you can also buy that foam spray from a home improvement store and make your own. A lot of people with dart frogs use it to make custom backgrounds. You can spray it on and shape it with ledges and duggouts for live plands, then cover it with coco fiber or moss while it's still wet to give it a natural look. I don't remember the sites offhand, but I'm sure you can do a google search for it. I've seen some really cool ones out there, and there's one site that has a good walk thru on the whole process.