Several types of SCA Coinage have been developed as an attempt to bring versimilitude to the game, and are frequently used for ransom (especially in ransom melees), taxes or paying mercenaries.
Typically, this type of ersatz money is inexpensive and edible.
Golden Splonders have been used in the Kingdom of the West as a type of coinage. Golden Splonders are, of course, chocolate chip cookies.
Chocolate Coins are an extremely popular form of coinage in the Kingdom of Ealdormere. These are the ubiquitous chocolate discs covered in gold (or silver) coinage, often in imitation of the Canadian one-dollar coin.
Custom made Coinage is sometimes created by artisans of the Kingdom for use as largess by the ruling Royality, The Kingdom of the West is belived to have started this custom.
Of course, all of this imitation currency is only used as part of the
game. Merchants' prices, site fees and other "real world" expenses must be paid in actual currency.