Kind of tangentially related to this:
I'd like to play a RPG with people that works in a very simple way - you play as yourself.

Players get together and spend a day customising their 'character' based on a number of pertinent questions. They're working on personas, basically.

And the 'game' is played about a year later. Ah, there's the twist. The 'game' is a wargame or other kind of sim.