Pearl farming and the secret society of diviners is an interesting look at how when you mix real world limits with the abstraction of fantasy rules, you get something baroque and cool.
There are several related posts, which adapt guild dynamics, medieval foreign and domestic policy, and similar constraints to build up a sordid world. The first article tackles adventuring’s horrific disruption of local society, and is followed by how guilds and vested interests push your magic items out of town, and a darkly conceived little war.
They’re all excellent from a twisted GM’s perspective–they’re tremendous world building. But man they’d be frustrating to experience as a player. They’re a great read, even if it’s not right to actually use this twisted and wonderful logic in your worlds.