Add to that the blue-water cruising sailing communities I've been fascinated with lately. It's kind of like camping, but on boats, and often concentrated in tropical areas where living is less expensive because energy needs are less and if you don't mind eating fresh local food, it's very inexpensive, sometimes free if you gather it yourself.

Of course there's a pretty high cost to entering that lifestyle. Typically, people drop out of modern life by selling expensive homes and other possessions they've managed to accumulate, then buy a sailboat and go where the winds take them.

The analogy is imperfect, because there's still the cost of maintaining the boat, and many states tax sailing nomads heavily or restrict the time they're allowed to spend within the borders of the states, even if they're on the water.

Nonetheless, it's fascinating to observe the cultures they've developed, the reciprocal generosity, the tight voluntary cooperation, and most of all, the freedom.