Kootenay Barter – Banking on Each Other

https://en.wikipedia.org/wiki/Ithaca_Hours (one of the larger systems, and the one Kootenay's was copied from, now defunct)

https://en.wikipedia.org/wiki/Local_currency (a general name for such currencies, with a list of a bunch of different ones)

https://en.wikipedia.org/wiki/Time-based_currency (not all local currencies are based on time but Kootenay Barter and Ithaca Hours were)

Although interesting, I should probably note that as a general rule, they have never seen high adoption, aren't very clear about what problems they're trying to solve, and seem to have minimal advantages over, well, any other solution. Even in places where a local currency system is nominally operating, you generally have to look very, very hard to find anyone participating (or indeed, who has even heard of it).

Also, the Kootenay currency has been defunct for something like 15-20 years.

But isn't that exactly debt? They give out currency which may or may not be backed by any available work at the time of redeeming.