My brother's in San francisco, living on a yacht (well, that's what he calls it anyway) in the bay. He picked up one to serve as an office for a vinyl printing business he has, and it worked out so well, he picked up a second and connected them for more space.
However, he spent a few $$ putting framing, some insulation and drywall on the inside (so you can hang stuff on the walls and run AC or heat reasonably well.
Being in SF, he got the boxes for almost free, though.