Other communities like Nerfighteria?

[Rosanna McGinnis]

I mean, there IS no other community as awesome as Nerdfighteria, but I am wondering (for some intern work): Are there other communities that are geared toward helping others/decreasing world suck and that have come into being because of an author or young adult book? I am specifically looking for communities that are mostly young adults/teens. I can think of the Harry Potter Alliance, but what others are there? Anyone?

[Marrisa B]

There's nanowriomo, on the teen section there's a long running thread called purple elephants. It's pretty awesome =) Come in & say hello.

[Wolfie Alas]

Another PE?! Who are you?