A crash course in changing the world.
A barter system that I am using that is unconventional is exchanging coffee for services here at The Citadel in my barracks. I purchased quite a bit of coffee, and I make it for people in exchange for multiple types of services or favors. The coffee cost about twelve dollars for a couple weeks worth and I am able to exchange a cups worth of coffee for a favor. Eventually, it becomes very obvious that I would receive more than twelve dollars worth of favors. That being said, left unchecked, I could use it to my advantage and exploit my friends. I can see how a similar system such as this could be used in a developing world to take advantage of the local populous. Using a small amount of money to purchase scarce resources in the area, then using those resources as a form of currency.