What is this? An earth oven. What does that mean? It's an oven made of clay which can attain heats of over 800 degrees. It can also hold a hot temperature for a long time. You can make pizza, bread, and anything else you would cook in a regular oven. However with the really hot temp of 800 you can make traditional italian pizzas in 3-4 minutes. With the clay and it's heat retention you can make superior breads. These guys are making 4 minute pizzas and selling them for 7 bucks.
There are all sorts of instructables on how to make one of these. Here's how I did mine..