What will really bake your noodle is simulating populations down to the last person. Let's just say it was something that was fun but not that much fun ;)
EDIT: of course by sim populations I'm also referring to the day to day running, interactions with each other and the player, a time frame system for actions and events in realtime with repercusions etc... etc...
EDIT: of course by sim populations I'm also referring to the day to day running, interactions with each other and the player, a time frame system for actions and events in realtime with repercusions etc... etc...