Take a look at the attached picture of a smaller yaht. Batteries for electricity are charged by the wind charger. It's hard to see, but hanging on the sides of the boat is a plastic solar shower bag -- which heats-up water for showering. The sail is used for moving the boat. How much more self-sufficient can you be?
I haven't been inside any of these boats (that's my goal the next time I'm in the Florida Keys). Most likely the yahts probably have a back-up generator or gas bottle for cooking. But all in all, I bet they use very little outside power to live on their boat. You gotta love that!
Mark
