[kkfx]

Like GNU Taler, who born out of eCash, born out of an idea of David Chaum in 1982 (see https://youtu.be/DDsQCcuST6c for a nice introduction) there was

- https://en.wikipedia.org/wiki/Mondex (Mastercard)

- https://en.wikipedia.org/wiki/Visa_Cash

And there is ongoing from the BIS https://www.bis.org/about/bisih/topics/cbdc/tourbillon.htm beside that there are many CBDC projects designed for inter-banks usages or some for wide public usage.