Fantastic! There's a book by Charles Stross called "Neptune's Brood" (https://en.wikipedia.org/wiki/Neptune%27s_Brood) where the central character is a historian specialising in these kinds of frauds. This includes futuristic versions where the 'Spanish Prisoner' is offering 'slow money' to in return for 'fast money' to help finance a new FTL drive:

> They're not poor: Here see these slow dollars signed by a bank a very long way away? Won't you hold them as collateral and front me a sum of fast money to help my friends make their repairs? We'll accept a ruinous conversion rate, just in return for the money we need to get our space drive working again; when the bank-countersigned certificates for these slow dollars reach you, you'll be rich!