What is the strangest/most creative form of government you have created for your world(s)?

Hey everyone! Let's try to get some more activity in here. I was wondering what kind of rulers you have all created. I realize most medieval settings will probably have a monarch rule the lands, but this does not have to be the case. So, what kind of governing systems have you created in your worlds?

I'll start off as I am making the post. My players are in an archipelago divided into five inhabited sections. One of them excersizes a system I have dubbed "Elected Sacrificial Monarchy." Bit of a mouthful, but the principle is simple. The people elect a mostly absolute ruler who will rule for five years. They can be granted two additional years in a re-election if they are popular enough. When their term, extended or not, ends, they are beheaded in public after a new leader has been chosen. There are clauses that can give exceptions in dire cases (defensive war or some other disaster), but they are rarely invoked.

The principle of this is that only those who wish to better their nation and are prepared to pay the ultimate price to do it will put themselves forward as a candidate to rule. It is by no means a perfect system, but I'm pretty happy with how it turned out. So, what about all of you? Did you have any unique governments in your settings? Tell us about it :)