Can you point us to a real-life implementation of the informal/barter economy? All I can think of are weekend flea markets and farmer’s markets. Perhaps people who travel with bands such as Phish could also be an example (doing business, not just drugs, in the parking lots). Could a sufficient economy be sustained around such occasional meet-ups, or would it require a permanent space, such as an abandoned grocery store or box store? Can it be sustained online, or through one-on-one interactions (with no public market space)?

Can it exist alongside wage labor, whether in the form of full-time work for a portion of the community, or in the form of part-time work for many of the informal market participants. It seems that full-time wage workers would have a hard time participating in the informal economy, but perhaps even just a little participation would be enough to provide some hard cash to the people in the informal economy.

I’m guessing that your answers would be “no-one can know” or “a bit of each”. I’m just trying to figure out what is the real sticking point to establishing a thriving peer to peer market.