This may be redundant information but I have come across a very interesting wiki-based game which provides a fun way of generating backstory collaboratively. It is called Lexicon and is a wiki-based RPG (or at least an RPG of sorts!) in which players each assume the identity of an academic/authority (who can be biased) and take turns to create 'encyclopedia' entries on specific topics while at the same time generating further topic headings for others to flesh out with their entries. Each new entry must be compatible with existing entries although 'facts' can be reinterpreted and opposing viewpoints put forward. As the game progresses, a richly linked 'historical reference' in wiki form develops, which is a weaving together of several individuals' creative inputs and has an undercurrent of intrigue due to the manoeuvring between 'authorities' to give history their own particular gloss. I will see if I can find a link to an example and post it later.