Over on DA I starterd 'Collective fable', a multi-authored visual story. I wondered if it might be nice to begin something similar here. It would seem suitable for this section. This is the DA version: http://collectivefable.deviantart.com/ with the rules, etc in the journal bit. A visual story could get started here without all the business of joining the club, all we need is someone to do the first scene. The linear structure of the forum thread probably suits a collective story better than DA galleries do.
I suggest something fantasy, but it's up to whoever starts it to set the scene.