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places to find fic (multifandom)

Yuletide- a secret santa fic exchange for "obscure" fandoms.  the highlight of my fannish year.
Silverlake- great multi-fandom archive.  all the basics, but specializes in the obscure.
Slash Cotillion- an archive for slash fanfiction about historical figures.
Fanfiction.net- the biggest fanfiction site out there.  contains some good work, if you can bear to wade through all the crap.
Crack Van: Multifandom Mobile Addiction- daily multifandom fanfiction recommendations.
Polyamorous Recommendations- Shrift and Nestra rec fic in many fandoms; they have rather excellent taste.
Femslash Today- daily femslash recs and links.
Girlslash- a multifandom femslash fanfiction community.
bastet on del.icio.us- my best friend's bookmarks; my own greatest source of fanfiction recs.  ;)

general fandom resources

deviantART- the web's biggest art gallery site, I believe.  absolutely teeming with fanart, as well as just about everything else.
The Fandom Symposium- an excellent collection of essays about fandom and various related subjects.
Fandom Wank- that infamous community dedicated to making fun of fans acting stupid.  mock well.
Fandom Counts- created in response to difficulties with livejournal: attempting to measure the fannish presence there.
Journalfen- a journaling service created by and four fans.  codes are required to join.
Minotaur's Sex Tips For Slash Writers- fairly self-explanatory, no?  helping people write gay sex scenes since 2001.
Heresluck- an excellent source of fanvid recommendations (for multiple fandoms)

fandom-related sites (of a more specific nature)

comics
Girl-Wonder.Org- a website advocating for female fans of, and characters in, mainstream comic books.
When Fangirls Attack- a daily-ish roundup of links related to women and comics.
Newsarama- A very good source of comic book news.
Pop Culture Shock- another good source of comic book news.
Scans Daily- a livejournal community for the posting of interesting, amusing, and slashy comic scans.
UncannyXMen.Net- a well-rounded X-Men fansite.  tons of character information, and issue previews.
Fem-X- an X-Men femslash archive.  has fanart, too.
Rachel-X- the only X-Men forum I still visit, all centered around my favorite character, Rachel Summers (Grey).
Spider-Man Will Make You Gay- Umm . . . yeah.

due south
due South Fiction Archive- the major fanfiction archive for the fandom
The Due South Noticeboard- a livejournal community for fic and other dS-related material
dS Closet- a Fraser/Vecchio-specific livejournal community

from eroica with love
EroicaFans.Org- excellent resource.  manga summaries, archived fanfiction, and the fan-forum.
Belladonna's Eroica Site- more fanfiction, and a few extras.
Schloss Eberbach- the main Eroica community on livejournal.
Castle Gloria- another livejournal community, just for fic.
Fried-Potatoes- still more fanfiction, and some fanart too.
Guide for Serious Eroicafen- a collection of useful links and articles

good omens
Lower Tadfield- general Good Omens community on livejournal (discussion included)
St. James' Park- a "less cluttered" Good Omens community (honestly, everything tends to be crossposted.)

harry potter
The Leaky Cauldron- very up-to-date Harry Potter news.
The Harry Potter Lexicon- the best compilation of information about the books and what's in 'em on the net.
JKRowling.com- the author's official website.
The Sugar Quill- a HP fanfiction and fanart archive.  somewhat infamous for its die-hard attitudes towards canon relationships.
Girls Today- daily Harry Potter femslash recs and links.
Restricted Section- a large adult Harry Potter fanfic archive, which opened after fanfiction.net banned NC-17 stories.
Pornish Pixies- an excellent livejournal community for adult Harry Potter slash.  requires membership.

smallville
Smallville Slash Archive- fairly self-explanatory, I think.  most every bit of slashfic written in the fandom ends up here.
Kryptonsite- a useful all-around source of news and information on the show, if you're still watching it.

stargate: atlantis
Gateworld- the major Stargate fansite, with news, interviews, and episode guides.
Stargate Atlantis Noticeboard- a livejournal community for posting fic and other fannish material
SGA Newsletter- daily SgA fandom links

others
Anime Lyrics- an extremely useful and extensive database of anime/jpop song lyrics and translations
KP Slash Haven- the center of Kim Possible slash fandom.
TheOneRing.Net- the biggest and most extensive of Lord of the Rings fansites.
TheForce.net- the definitive Star Wars fansite.
The Agency- the central Once A Thief fansite and fanfic archive.
Tom's Xena Page- pretty much the best X:WP resource around.
Battle On!- wonderful Xena spoof-comic.  stopped updating long since, but still fun to read.
Teenage Wildlife- this was the David Bowie fansite.  It has ceased to update, but still has all the lyrics.
CROTCH!- a site dedicated to Bowie's . . . area.