In WWII prisoner-of-war camps, cigarettes functioned as a real currency

In prisoner-of-war camps during World War II, inmates received regular Red Cross parcels containing, among other things, cigarettes — and it was cigarettes, not any official money, that became the camp's real currency.

The twist: the system was surprisingly economically mature — there were established cigarette "prices" for various goods and services (from chocolate to laundry), the exchange rate fluctuated with supply shipments, and there was even a form of credit and lending between prisoners.

One of the prisoners, a trained economist, later described the phenomenon as a scientific observation of a living market that emerged spontaneously, with no central institution or bank whatsoever — purely out of the need to trade goods under conditions of isolation.

The stakes: this case is still cited today as proof that money doesn't need to be established by a state — any good that's scarce, durable, divisible, and accepted by the group is enough for a community to spontaneously build an entire economic system around it.