My in-laws built one of these in the mountains of New Mexico north of Tijeras. Not quite this extreme - they stopped short of the indoor plants and bottle walls, but 3 of 4 exterior walls were rammed earth in tires, giant south-facing windows to maximize solar gain in the winter, off-grid solar and a metal roof to catch water. It looked really nice (walls were finished with stucco) and was in a beautiful spot on a south facing mountain slope. They eventually sold it for a live aboard boat, but it was an incredible place for the couple decades they were there.

I would love to live in an earthship. I will say, builders/owners should develop an instruction manual for all of the off-grid systems. They're all a bit unique and visitors will be totally unfamiliar with their operation and peculiarities.

One of the cool things about these homes is how creative the designs are. How they design to amplify and harness the environment around them. Be it light as @k00b points out or the heat of the sun.

I love earthship homes! If I ever get around to taking a vacation I want to find one I can rent for a couple weeks.

When I first heard about them, I was spending all of my time working on my laptop outside so I could get a lot of sun. One of my favorite things about the design is that it lets in so much light.

Earthships are very cool.