Such so-called complementary currencies — a broad term for a galaxy of local alternatives to national currencies — have been around for centuries; according to research published in the journal Papers in Political Economy in 2018, 3,500 to 4,500 such systems have been recorded in more than 50 countries across the world. Typically they are localized currency that can only be exchanged among people and businesses within a region, town, or even a single neighborhood. Many are membership programs limited to those who have signed up for the scheme; they typically work in conjunction with rather than replace the official national currency.

https://www.bloomberg.com/news/articles/2020-08-07/a-depression-era-idea-gets-a-new-look-local-money?srnd=premium&sref=EcccZSTc