N55

Danish artists and activists at N55 developed the walking house so that one could live nomadically with little environmental impact: energy is collected via solar cells and small windmills and a small greenhouse module can be added. And not only can it collect rainwater, it's amphibious.
N55 says "The Walking House requires no permanent use of land and thereby challenges ownership of land and suggests that all land should be accessible for all persons. Society could administrate rights to use land for various forms of production of food for example, but ownership of land should be abolished."
TreeHuggers may remember N55's micro dwellings, similar but without the walking legs.