Tupperware House Homemade RattyRat's Review: Are you on a budget? Here is a great idea for a homemade den, and it lasts a lot longer than cardboard boxes. Take an old tupperware dish, or plastic container of suitable size, and cut an opening into it. (I used a soldering gun to cut mine.) If you can find a plastic that is not see through, it is preferable. Walla! You have an easy to clean, long lasting den for your ratties cage.