Yesterday there was a "Why aren't you a game developer" thread and that gave me this idea. It might be a terrible idea but that's where you guys come in, your job as devs is to make this bad idea a great idea.
I don't have many details worked out, but you might play a forum mod, your job is to grow a healthy community. The site makes it's money from advertising so the more eyeballs the better. Or perhaps you're the disruptive type and you want to start huge flame wars and make the mods job as difficult as possible, this would reduce the forum's population and hurt advertising.
So possibly, there are two ways to play.
Todo
1. how would you simulate posting and thread discussions?
2. how would you make this challenging?
3. lots and lots of other things.