Cats have a thing for cardboard, but a plain old box doesn't do much for your decor. Instead, tuck felines into this Modernist chalet ($23, loyalluxe.com). The faux-bois cabin, made from recycled cardboard, is shipped flat for extra eco-friendly credit.
The Roll-a-Nest (from $5, at pet stores) looks like a decorative object but encourages natural nesting instincts. Woven from sisal, the hideout doubles as a snack for guinea pigs and gerbils in need of a nibble.