It is possible to live off the grid, in a home that is mail-ordered and shipped directly to whatever site a home owner designates. As discussed in this recent article, House Arc is the one of the latest in what seems to be a steady stream of green, modular housing models.
Architect, Joseph Bellomo, inspired by the disasters of Katrina and ones similar to it, designed House Arc homes. Rather than require victims of disasters to live in trailers or sub-standard housing, House Arc homes, offers an alternative option.
These homes are roughly 150 square feet, can be shipped via a flat packing container and assembled much like a piece of Ikea furniture. They are super easy to construct (assemble) and deconstruct, especially for someone with basic carpentry skills.