Blood
From NSwiki, the NationStates encyclopedia.
Blood is used by many nations as currency. In Zumorito it's value depends on blood type, and amount of blood. Usually capsules, bottles or bags of blood are carried in various amounts. Interestingly enough, in Zumorito, advanced cash registers allow you to directly inject the blood into the machine, and it verifies the amount and type of blood. The rarer the blood type, the more valuable.