Have you ever purchased a new refrigerator to find that your children play with the empty box for weeks, instead of playing with their expensive toys? Now is your chance to capitalize on this phenomenon. Custom cardboard playhouses are great for kids. They're mobile and can be packed up easily and moved to the beach, Grandma's house, or outside in the summer. To get mobilized in this business, simply design your own playhouse and visit a box manufacturer for an estimate to produce the cardboard playhouses in volume. The playhouses can be sold via retail accounts, mail order, the internet, craft shows and flea markets. Design tip: Be sure the cardboard playhouses will be interesting to children, and make sure there are a lot of colorful images and themes printed on them.