What to do with my empty 18x18x24?

[MrCaveman]

I have an empty exo terra 18x18x24 sitting on my desk and wondering if you have several suggestions to put in it. Currently im debating on this or a small reef tank but.... the reef im afraid would be a little too demanding for what I want. So please make some suggestions, Im just tossing around ideas for now

Right now im thinking of a dart frog tank or possibly a paludarium with a water bottom for a few fresh water fish with maybe a tree frog, anoles or geckos.

[boosh96]

May I suggest a pygmy chameleon? They're really neat little guys and they can live in a vivarium. Here's a link to a care sheet if you're interested.
Chameleon Forums - CCR - Pygmy (http://www.chameleonforums.com/care/caresheets/pygmy/)