The main housing I use for the ratties are double Critter Nation cages. Each double is split in half with three halves for the males, and three for the females. I am working towards getting all of the deep black pans to help with litter scatter. They're large cement mixing bins, found at Home Depot or Lowe's. You have to trim about 1/2" off the rim so it fits in. The clear bins on the smaller shelves are 28qt with 23"x16" dimensions. They help tons with keeping litter in! I house 5-6 females or 4-5 males per half. For nurseries and breeding cages, I use the Ware chew proof cages below. I've got four of those, which helps limit me to four litters at a time. Anymore than that, and it becomes hard to give enough of my time to each litter. I used 90qt bin cages before, but had some recent escapes from young ratties chewing out. So far, I like the new cages though! When babies wean, I typically add them in with my adults in the Critter Nation cages as long as there is space. This allows them to learn social behaviors from the adults before they head off to their new homes!
For my fancy mice, I have two 64qt bin cages for grow-out and female only cages. For breeding/nursery cages, I use 12qt bins. The larger bins have wheels (not in the picture, it was getting washed), baskets, hides, and lots of chews and nesting material to keep them engaged! The smaller bins have hides, nesting materials, and tunnels.
Prairie Dogs **I do not breed these guys. They're just my pets!
The layout for their cage is always changing to keep them engaged and from getting board. This is to just show the general look. I've got three sweet prairie dogs right now; Oscar, Daisy, and Rain.