Tristan sez, "Open Source Ecology is a social enterprise based in Missouri. We develop open source machines that can be made for a fraction of commercial costs, and share our designs on the Internet for free. We've just designed version 4.0 of our compressed earth brick press, the Liberator. With this machine, anyone can make solid, 'dirt cheap' structures from the earth beneath their feet. This linked video shows the evolution of the CEB press from 2007-2012."