Nice, I've never seen that but I'm going to read that whole page. I think that's probably correct about complementary currencies, if they're just currencies. I wonder if it would be different if each of them had actually different properties?

The cool think about tokens is that they can be programmed to behave different ways. Can you imagine a world where each currency is programmed differently? For example, maybe one currency gets deflated with each transaction (gets multipled by 0.9), and another currency can only be sent a certain number of times before it disappears, encourage people to hold it. Can you think of use cases where that changes the utility of a complementary currency? I'm asking because I can think of a few, but it's so hard to tell whether or not they're good ideas.

The second part, outside of that, is that tokens are on a blockchain. Again, none of this is specific to us, but there are a few properties that any token gets. Namely: They are provably scarce, they can interact with smart contracts, and they can be traded for other currencies if necessary.