If you really want to get into it, bromelaids and certain orchids can do well in a terrarium, but they require more specific maintenance and conditions, so I'd start with the "bulk-cheap-plants"
I got some "bulk-cheap" bromeliads from Black Jungle, $3 each. They are doing great. Well, most of them are doing great. The one I put in with the clown treefrogs died, the enclosure is unlit.
Originally Posted by adawinters
Some part of me would love to decorate my leopard gecko tank w/ plants, but it's too arid for anything but cacti, and that's not really safe.