A world whose lands are made up of huge terrain spheres that rotate constantly with most portion underwater. As time passes, the shape of the bodies of water change, landmarks shift inside the new border lines, and mountains tilt to different degrees. Land dwellers are gypsies that can never build anything permanent, and somewhat ironically, the only stable settlements are large structures built at sea.
Custom among pirates to yearly vote for their leader. If a majority believed the leader was doing poorly they could hold another vote. Democratic except in times of battle and danger at sea. Could bleed that over to some 'honorable' bandits.