Chameleons present exceptional challenges in what materials you may safely use and the way you design the enclosure. There are several varieties of enclosures available on the market that may be used to house chameleons.
I'd love to have a small-ish indoor touch tank with sturgeons and small rays and dogfish (sharks) in it. Preferably with glass at at least one side, so you can see them swim around. Small-ish being single bedroom sized.