It is still whole! He made another one for one group of my Winter Whites Russian Dwarf Hamsters but they were happier using it as a hidey-hole than a sleeping area. I also use empty men-size tissue boxes and the cardboard inner tubes from kitchen and toilet rolls. They all love empty egg boxes and the Campbell's Russian Dwarf Hamsters usually end up sleeping in there... It is so cute to open the box and see them peer up at you from their egg-cup! You can fashion boxes from all sorts of empty outer packets in your kitchen cupboard - just make sure they are clean and non-plastic coated. Don't use sellotape, staples or glue if you can, but practice oragami and paper-folding techniques to join edges
Whilst trying to make a coconut house for a present it unfortunately broke so my partner, Jules (I should introduce him at some point as he does help with the hamsters a lot - he is my chief tamer!) cut it around the middle using a small saw into a half shell, and drilled four holes around its edge. We then hung this with string from the roof of the enclosure (a bit like a hanging basket). This is in another of my Winter White Russian Dwarf Hamster enclosures and they climb up into it and swing from side to side, a bit like in a hot air ballon! I will have to get a photograph for you all
If making something like this just be sure your roof will support it AND the weight of your hamster, plus any treats or bedding it takes up there, and be careful they don't chew through the string so it falls and hurts them.