Regarding containers that ship themselves, aside from the piracy issue, and making sure that the full container plus accessories was still buoyant, I suspect there are economies of scale that make it more fuel-efficient to gather thousands of containers on a single boat.  (Now, a robotic <i>sailboat</i>... hmmm.)<p>Some architects have designed houses made from recycled shipping containers: <a href="http://www.thedailygreen.com/green-homes/latest/shipping-container-homes-460309" rel="nofollow">http://www.thedailygreen.com/green-homes/latest/shipping-con...</a>