You might be familiar with the two cows method of explanation. I think the origin is a way to explain the differences in political philosophy. You can find a good list at the Illinois Gies College of Business. Here’s an example;
FEUDALISM:
You have two cows. Your lord takes some of the milk.
PURE SOCIALISM:
You have two cows. The government takes them and puts them in a barn with everyone else’s cows. You have to take care of all the cows. The government gives you as much milk as you need.
FASCISM:
You have two cows. The government takes both, hires you to take care of them, and sells you the milk.
Robert Wiesehan has a roleplaying game systems alternative of the two cows system. It runs the gamut from D&D, Pathfinder, through Shadowrun and to Fiasco.
Is your favourite system represented? If not; how would you describe it?
Creative Commons cow by Amezzi.