
1) Card Keys
This building was built from 200,000 card keys. Each room and every wall, even the toilets, are made of card keys. The hotel was built by Bryan Berg, who has a world record in building a house of cards. (Link)
2) Containers
The Tonghe Shanzi Landscape Design company has built their incredible five star Xiang Xiang Xiang Pray House hotel entirely out of shipping containers! Looking like a drab shipping container...