most recent discussion was about economic systems. Here's a snippet of her summary. If you scroll down, you can click to watch the conversation.
One of the really critical things that can grow out of understanding how people are paid, and in what form, is a sense of how the social system works and where crime arises, and why. I spent a bunch of time working out how different members of the Varin undercaste would be paid, and when I did, it really changed everything about how I understood them. The trash workers, who are paid in cash, are naturally subject to attack by thieves who wish to make off with such an easily reusable form of money, so they band together into gangs to protect themselves. The prison workers are paid almost no cash, but have their housing and clothing and food paid for by their employers, which makes them into a sort of undercaste "impoverished nobility" - because they are taken care of, but they are trapped in their situations with no ability to flex to circumstance. The crematory workers are paid in housing and clothes, but not food - and they receive cash, because it's not a job most people want to do. The association of their work with death makes it so that nobody wants to steal their "death money," but at the same time, they are something of a pariah class even inside the undercaste. The real value in exploring this kind of thing in detail is that critical story elements like crime and the need for self-awareness in the street, for different social groups, is motivated and explained on a really basic level, and the world's sense of reality is immeasurably enhanced.
Small details of economics lead to enormous consequences for the success of your worldbuilding.
Genre, anything that takes us away from the realities of our own world, makes a great vehicle for questioning how we do what we do. It allows us to move outside our assumptions and privilege groups. Research on our own world, and its cultural subgroups, is super valuable here.
Currencies are all about belief. We discussed a real-world situation where some economics professors were able to bring hyper-inflation under control in Brazil, by creating a second currency whose value was constant while the other currency's value fluctuated. By paying people in the stable currency, they were able to create a real sense among the public that the currency was stable, so when they finally converted to it, the hyper-inflation problem stopped.
We also talked about magic as an economic system. Magic is a resource, and if it's not used properly, you can end up with Magic Inflation. If magic has no cost of use, and is too easy to use, it ends up being used all the time, to the point where nothing you can do magically will have any value because it's all just to common and easy! What is the price of magic? This question can not only be practical, but an incredibly good driver of conflict in your story. A great example of magic used as an economic system is in Janice Hardy's The Healing Wars. Reggie told us about her work in progress, Spectra's End, where magic can't be counted on because talents are too random and can't be replicated; when people with a magic skill die, their ability is lost and people have to fall back on real world solutions.
Consider also the money vs. time equation for your society. Who has money? Who has time? It's hard to be a person with both, and even for those people, they may be paying in some other form.