Coroplast

Coroplast offers unlimited cage options for small pets. I'm amazed at the designs I've people come up with using coroplast. Easy to find it at sign stores and grid are readily found, as well. The only problem I've seen with them is that they aren't as sturdy as a heavier plastic cage. Could be an issue if you have predatory animals in addition to the prey animals in the coroplast cage. Still, as good alternative to a store bought cage.

Pros: Inexpensive, easy to make

Cons: hard to make a cage cover

I have a two story guinea pig cage that I made from coroplast and metal storage cubes. The coroplast makes excellent flooring that is durable,waterproof and easy to clean, which is important when you have four guinea pigs like me. The guinea pigs also have a ramp made from coroplast that goes to the second story. The piggies have no problem getting up it. I've seen all sorts of accessories made from the stuff, your imagination is the only limiting factor. Coroplast is also easy to work with

Pros: It is cheap and can make all sorts of things for small pets

Cons: None