Economics is one of those topics that should never be skipped in worldbuilding, whether in realistic fiction, science fiction, fantasy, etc. It's such a basic underpinning that a world will feel flimsy without it. You've got to know where resources come from, and why the rich people in your world are rich. Do the rich people own land? Are they merchants with good connections?
Think of the English impoverished nobility, a concept I always struggled with when I was a kid and simply associated noble with rich, without actually understanding the underlying economic issues. You have nobles trying to get money by marrying merchants, merchants who want to buy into a title because it gives them political or social legitimacy, etc. There are lots of very specific consequences, which we spoke about more than once in the course of the hangout. Maintaining appearances is a really important one, whether that be conspicuous consumption, or simply having a few expensive things to allow a person to "pass" in a critical interaction, such as someone who wants a bank manager to take them seriously. When there is a general sense in a society that poor people are not worth engaging with, it's critically important to consider what those people can do to get themselves looked at differently.
What is money like in your society? We get used to seeing paper money, but lots of different things have been used for money throughout history (rice, rum, etc). If the government makes too much money, you get hyperinflation, which actually first appeared among the Mongols! In designing my Varin world, I have spent quite a bit of time examining the different ways that different castes look at money and its value, as well as the ways in which they use it.
Reggie has a system based largely on items that can be traded. Landed people there tend to be okay because they have things to trade, but shopkeepers end up in trouble, because they don't produce anything, and not everything they have is necessarily useful at any given time. Hunters always have things to trade, but the underlying identity of the items restricts their utility as trade goods (one of the reasons why people have moved to money systems). Glenda mentioned that old country doctors were often paid in chickens!
If you're dealing with currency, you don't necessarily have a single currency controlled by the government. You can also have guilds, each with their own currency. Which currencies are reliable? Or you could have lots of small interconnected kingdoms with different currencies. How sophisticated are the means of payment? Is it all cash? Is there such a thing as banks, checks, credit, debit, etc?
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.
One of our discussants mentioned a real-world situation in which the women of a local society would make their own form of money using leaves and rubbing. It was a handicraft fit in between other tasks, and as such had value. Large ones would be worth more, and they would dry out and become tradeable. The system was dying because exposure to external money systems was undermining belief in the currency.
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.
Magic users become targets when their talents are in demand. You can build economic connections between armies, kidnappers, magic users, healers, and merchants in this way. Glenda talked about the "gilded cage" - where a magic user would have everything she/he wanted, but not be able to escape obligation to someone who needed those magical skills. They could also be asked to do things that are distasteful or immoral.
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.
Thanks to everyone who attended! This Thursday's discussion, on 11/6/14, will be The Culture of Sports, so I hope you can come talk with us about it. Remember, Daylight Saving is over so keep your eye out for 11am Pacific Standard Time. See you there!