Robert E - Thanks for the links. Just scanned over the first one - not your average shipping container by any stretch. Incorporating containers, or even components from containers, is an interesting concept and would likely satify most of the codes requirements. Instead of looking at each container individually for structural integrity, it's now a new type of pre-fab panel that is part of a larger system. Few here would consider slapping a couple of 2x4s together to span a 24' roof as rafters a good idea, but add web members and rigid connections at key points - engineer a truss - and most would agree it is a viable option.
Obviously climatic conditions vary widely around the country and each area will need to look at the most restrictive requirements for those local conditions. While significant portions of NYS can use precriptive design methods, there are some parts of the state that cannot, ranging from wind issues on Long Island to snow load (and even a small area of seismic concern) in the Adirondack Mountains, and that's just one state.
Reusing existing materials in innovative ways is one of the best ways to reduce both waste going into landfills (or on our back roads...) but energy consumption as well. Processing used metal back into a new product not only uses huge amounts of energy, transporting the scrap out to be processed and then transporting it back as the new product uses tons of fossil fuels. Reinventing the existing product, with little energy investment in the shipping or processing sides would be one of the greenest ways to build I can think of. Of course in the long run, they will need to be an economical product as well. Not just 'cheap', but provide true value - more bang for the buck.