Kurds and Castaways

"...the Skipper trades his fish for Ginger's decorative shells, not because he wants shells, but because he knows he can trade them for Gilligan's coconuts. The price of a commodity is its exchange ratio for the most marketable good, e.g., 12 shells per coconut. The value of the shell money is based on the goods it traded for yesterday -- since we can't know what prices will be today. Right now, the Skipper is willing to trade one of his fish for two coconuts, and he knows that Gilligan was recently willing to trade his coconuts for a dozen shells each, therefore the Skipper wants to price his fish at two-dozen shells each: enough to buy two coconuts. "

The above quote is from the best article I've read about the astounding post-invasion growth in the value of the pre-invasion Iraqi dinar. Read the whole article here.