I have been looking at the idea of a cardboard house.
Stutchbury and Pape's House of the future : Cardboard
Here we have a recent invention of a cardboard house...100% cardoard and fully waterproof. It cuts costs in many different ways.It is made to reduce costs of housing and is environmentally sound. Low costs in transportation.
You may not want to live there permanently however the cardboard house would be good in situations such as in an emergency or live in it whilst your permanent house is being renovated.