Kitten cage with loft bed...this makes the cage experience a little more interesting and comfortable, while not taking up a lot of space. We use collapsable travel cages, which are easy to take to  foster families on loan.  The loft beds are made of garden trays, which have holes in the bottom to thread plastic lock ties through and attach to the sides of the cage. We also use a small plastic garden lattice as a ladder. All of this can be easily cleaned and bleached between uses. The kittens do really well in these cages, but we also try to take them out for a bit of a run around at least once a day.