These types of cages are pretty common. I think the most popular would be animal plastics. They are a little bit different, but same concept. Most of the people who keep snakes in anything but tubs will use this type of thing.

A few other reptile enclosure manufacturers:

Boaphile (though I hear ordering online doesn't really go so well)
Vision Cages
Animal Plastics

A quick google search for reptile cages will yield some results. I think these enclosures are very cool for display animals, but not so great for the constantly hiding ball python. Just my opinion