I will have to say that I loved the hospital cage, and if I ever needed a small brooder I'd love to do it this way. I had a 10-gal aquarium (larger would be better) that had a top fitted for small animals. I just put a lamp over one end, and a heating pad under the whole thing. It is large enough for a quart waterer, but they mostly ate and drank from small condiment cups I kept in there (then the banty slept in the cup when he finished eating!).
I LOVED having them so visible and up close. It would be a great brooder for a few banties, or just a couple of chicks. It was great for keeping them warm and blocking drafts too.
(And the new kitten enjoyed watching the fuzzy things through the glass, but I don't think he realized they wanted to eat HIM ... at least catch his tail! The kitten is weird anyway, kinda like Judymae's. He plays with the gerbils through the glass as if they were other kittens, not as if they were prey. He acts like they are his buddies and wants to sleep with them.)
trish