I keep my chameleons on their Ficus plants when I clean out their vivs usually. Or in some cases, a large branch if they happen to be on it at the time. I remove my chameleons from their viv on whatever they happen to be on (plant or branch) and leave them on it.
I happen to be one of the buyers at That Pet Place and I actually buy all the hagen products that we carry. That specific product is called the exo-terra explorarium. If you type in explorarium at our website www.thatpetplace.com all three sizes will pop up for you. If I remember correctly they're $22.99, $32.99, and $52.99 for small, medium, and large respectively.
I set up a jungle gym for Luna and she loved it! When I did daily cleaning she was usually in her cage, but weekly full cleaning I would open her door, attach her little rope "ladder" to a silk pothos in her cage and up she would go. I used sash cord and small cup hooks in the ceiling. I draped it all over the room and then attached it to a bracket above the window - which was always her final destination! lol! I had it so that she could not get anywhere unsafe. I have pics if you want to see. I think I have some at webshots.com (username: 13lele)
I have some showing the whole setup (from cage to window,etc.) I will have to find them and will post (if I haven't in the next day or so feel free to remind me!). I got the idea from a cham keeper on another forum, a few years ago, who used bungie cords. I live in NH so the "gym" gave her lots of exercise during the cold months!