Hello Market Economics Fairy. Shift perspective a bit: What's one step above the concept of money? Any government (or in Hong Kong, any bank) can print FIAT c

Hello Market Economics Fairy. Shift perspective a bit: What's one step above the concept of money? Any government (or in Hong Kong, any bank) can print FIAT currency, arcades trade cash for gameplay tokens, parking structures sell vouchers to park a car for some set period of time (which employees might get for free if they work in the building). What establishes the value of each, beyond trust, reputation, and demand? How could someone go about designing a wallet full of wallets, that could hold any type of money from any country or organization, where no value was established implicitly, but that simply allowed any organization (or individual) the technology to print money that could not be counterfeit? What is a dollar bill other than the signature of the US government? What is a Euro other than the signature of the EU? What is the exact value of the signature of Michael Jordan? What if your wallet, instead of holding money, simply held any type of signature?