Hutches are definitely not recommended as they take up far more room if you are able to build one yourself, and are far more expensive in any case. They also smell as they just soak up the urine and this can cause possible respiratory problems.
In the gallery there are pictures of enclosed cages, the wire shelving or leftover cubes make an ideal top - just make sure that only you can open it and not your cat! You may find your cat likes sitting on top of it but the piggies will soon get used her
