Debt: The First 5000 Years by David Graeber, Melville House 2011
It's a whole book, so I can't do it just with excerpts, but basically, it's the story of how we got to where we are with money.
There are things for both right and left economists to hate here. Essentially, Graeber looks at the anthropological and historical record and claims that the orthodox economic view, that barter was replaced by money, is over-simplified and even wrong.
He also talks about attitudes toward debt through the ages and in different cultures (some consider it bad, and others consider it good), how war and money reinforce each other, how attitudes toward money have tied in with religious beliefs in various cultures, how customers and merchants paid one another through the ages and around the world, and how major economic theorists through the ages have over-extended the circumstances of their own societies to make broad generalizations.
You won't agree with everything in the book, but it will make you think, and that's never a bad thing.
Available in dead tree and Kindle versions.