Fic asylums
There are a variety of multifandom fic and icon communities popping up, such as tv_100 and rarecharacters. Some Whedon ones:
ats_btvs_fanfic a community for fanfiction based on either Buffy the Vampire Slayer or Angel, accepting fanfiction focusing on all pairings, characters and ratings.
five_by_five A Faith Lehane community for discussion, fanfic, fanart & graphics.