Second Life Tax Revolt
I've always found Massively Multiplayer Online Role Playing Games (MMORPGs) facinating from a sociological perspective: how the economic system develops over time, for instance, or how "real-life" social groups and relationships get expressed in virtual worlds.
Second Life is a relatively new entry that borrows from the old MUD model: it allows the inhabitants to create new objects and structures with associated behaviors. Cool -- let your user base keep things fresh.
Well, back to the point, in order to combat the hyperinflation that has occurred in other MM games, the developers decided to institute a graduated tax. The article "On the Second Life Tax Revolt" looks at how the players in this world revolted against this tax within the constraints of the world itself. Neat stuff.