How legends are made

This is my idea of the moment, a game about how legends grow in the telling, evolve and get hijacked.

The idea is akin to Chinese Whispers, the first player gives a very basic story then it gets passed on and influenced by events conceived of by the next player, then the next, and so on until it changes out of all recognition.

So, for example, the story starts as "man defends family against landowner", which becomes "Man defends village against wicked local baron", which becomes "Man leads heroic defence against oppressive king, who is in league with dark power", etc

I'm thinking of something fairly abstract (like Baron Munchhausen maybe), with some way of representing how various institutions hijack myths for their own ends.

Currently I'm inclined to have each player take on the role of church, state, art or science. They get points if they move the story towards their own ends. They lose points if they move the story too far from the last iteration.

As to the mechanics of how this actually works, I havn't really decided, so I thought I'd throw it open to the Forum for suggestions.

Matt