In the latest issue of Details (yes, Details), there's an interview with a man who lives in a cave and does not use or accept money or barter.
And is so happy with it he maintains a website about it using public library computers.

Daniel Suelo says he has been living without a cent to his name since 2000, dumpster diving to make use of the things the rest of us throw away and living on wild vegetation and things you and I would never touch.
On his site's FAQ he talks about why he finds this sort of life (informed by Christianity, his time in a Buddhist monestary in Thailand and among the Sadhus of India) incredibly spiritually fulfilling:
"Mixed with my kid instincts, I grew up in an Evangelical Christian home. I took my religion seriously. But I started wondering why professed Christians rarely follow the teachings of Jesus - namely the Sermon on the Mount, namely giving up possessions, living beyond Credit & Debt, freely giving & freely taking, giving, expecting nothing in return, forgiving all debts, owing nobody a thing, living beyond payback of either evil-for-evil or good-for-good, living and walking without guilt (debt), without grudge (debt), without judgment (credit & debt), living by Grace (Gratis, not by our own works but by the works of the true Nature flowing through us)."
I have no conventional religion left, but don't think I could live like this even if I did.
I do, however, wonder if trying it might not teach one a lot about himself.
What do you think?