Have you ever wanted to start a roleplaying campaign with some control over what characters PCs generate, but not wanting to have full control? Or not wanting to have to write up entire histories for characters that will most likely be ignored by some of the player?
I'm not sure if folk have done, or thought of this before - but I had the idea of partial pregeneration. Break down the key elements of your setting into small chunks, and let the players choose from them. You can even have the chunks be entirely fluff, divorcing them from the rules of the system you're using - just put in a simple letter code for each segment.
Ideally I view this as being some kind of card system. This limits how much fluff can be written for each setting chunk, and makes them more standardised in appearance. The added advantage being that players can keep the cards and view them is key plot points for their characters. It's all well and good to have on your character sheet "brown hair and weighs 78kg" but it's fairly pointless when compared to "grew up in a village devastated by fire" when compared to how it interacts with the campaign and NPCs.
So the way I picture this happening is you have certain sets of cards. Sets could be particular times in a character's life, or they could be particular personality traits, skills, talents, powers etc..
If players have particularly creative ideas, you can also dispense with particular sets of cards - only using as many as you want control over types of PCs in the campaign.
You go around the group say, starting with a set you've created called "place of birth" and you work your way through the cards in a predetermined order (this could be - most important to the campaign to least, or it could be most gameplay benefits to least, or any other order, or random etc).
"Who wants to come from a small village near the coast?" - give the card to any takers. If you have multiples, make sure you have multiple cards - and have a contingency for when players have the same card - are they from the same village, or different ones?
"Who wants to come from a small village near the mountains?" and so on...
On the cards you have a letter code that you can jot down in your GM notes for future reference - and if you need to lock in system mechanics to card choice.
You can use this mechanic for other parts of a campaign too-
NPCs - take the cards the PCs chose and deal one or more randomly to the NPC - this is what they have in common with the party and can be a talking point for them (similar traits/personalities or backgrounds)
Plot elements - take the cards the PCs chose and deal one or more randomly out as the subplot to the main plot - it determines which character(s) may be the focus of the subplot.
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As an addendum to this - just tried a google search for storytelling settings as some way of making generic cards/chunks for use/demonstration and came across this rather nice website-
http://www.skotos.net/articles/ELEMENTS.shtmlSomething to look at later.