Military Payment Certificates (MPC) range from 5 cents to $20 and were used specifically overseas by the military and authorized civilians. The Secretary of War approved their use 7 August 1946. They were first issued 16 Sep in Europe and 29 Sep in the Pacific. They are no longer used as currency.
Items for trade or sale, just make an offer. (click to supersize the scans)
Most of these are currently listed on eBay if you are intested in picking something up.