Not a fancy floor but certainly interesting and innovative. How to create a floor for your house with mud. 

Here are some pros and cons of installing an earthen floor.

Advantages of earthen flooring:

• Eliminates construction waste – excess earth can be reincorporated into the landscape
• Attractive, comfortable, slightly spongy surface, sometimes compared to leather
• Inexpensive materials
• Minimal to zero pollution – Earthen m aterials require only simple processing and little or no transport. Even when produced by a machine, a finished earthen slab is estimated to have 90% lower embodied energy than finished concrete. 
• Durable with proper care, and repairable
• Low maintenance, able to be swept or moist-mopped; properly sealed, stabilized earthen flooring is not dusty

Disadvantages of earthen flooring:

• Labor intensive to install
• High traffic areas such as entries or workspaces may require additional materials – such as flagstone – for protection
• More vulnerable to scratching and gouging than hard tile or cement – but earthen flooring is more durable than vinyl because it is repairable.
• Few local contractors are experienced with earthen flooring