(note: most things listed here are yaoi or shonen-ai in nature)
Recommended reading:
Firecat Fanfics
Natalie Baan's Sakura and the Snow is a beautiful, simply beautiful Tokyo Babylon fanfic that takes my breath away.
The Turnip Patch
Jei's gorgeous Gundam Wing series, Moments of Haven, was a partial inspiration for My Heart to Joy at the Same Tone. The best portrayals of Heero and Duo that I have ever read. I also recommend the a/u series, "The Best-Laid Plans."
Toffee's Layer of the Weird
Toffee writes beautiful Saint Seiya angst fics. I recommend Unbroken and the super tragic sequel, Flight on Torn Wings.
Fuu-chan's House of Dreams
Fuu-chan writes BRILLIANT cross-overs, no easy task. My favorite is the X/Saint Seiya cross-over, Yours Ever, though I like her Rurouni Kenshin/CLAMP fic about Saitou and Tokio.
Coronation at the Yaoi Shrine
And of course, no Arslan fanfic site would be complete without a link to Sahari's superb Arslan fanfic, probably THE best Arslan yaoi fanfic series out there, Coronation, the fic that got Angel hooked onto Arslan fanfics.
Recommended reading by Net friends:
Asgard's Crypt of Doom
For a HILARIOUS Saint Seiya fanfiction, go visit the adorably evil Torquemada's page and read "How Thor lost and found his axe". Then read her brilliant serious series about the Asgard warriors, The Rainbow. More of her wonderful Saint Seiya fics can be found on Stayka's Saint Seiya Fanfiction page. I recommend especially my all-time favorite, The Zeus Chapter which has left me rolling on the floor clutching my stomach in pain, and the equally funny "Five Saints." Heavily, heavily recommended!
Katei
For manga/doujinshi scanlations & translations, great fanfics, superb original fics, and just all around good fun, go visit my friend Cai's page. ^__^ She has a great Arslan/Guibu series.
Universum
For beautiful X and Tokyo Babylon Fanfiction, go to T-chan's page. I especially love "Dragon's Dance" and Dragon's Heart". She also wrote a gorgeous X/Soryuden cross-over, and is the only person whose Gundam Wing fics about Wufei/Treize that I like.
Real-life friends (haha! I know these authors!)
Celeste1's Fanfics at Fanfiction.net
My kouhai Celeste1 writes Fruits Basket fanfics and fanfics from various other series.
The Crown of Sand
My sempai Yui Miyamoto writes X, Tokyo Babylon, CLAMP, and Gravitation fanfics.
Tsusami's Fanfics at Fanfiction.net
My other sempai Tsusami writes Inu-yasha and Fruits Basket fanfics.
Rose Petals and Cherry Blossoms
Slayers Fushigi
Sempai Ming-Ling writes crossover fanfiction. The first is a Card Captor Sakura and Utena. The second is Fushigi Yuugi/Slayers.
Published authors (not really fanfiction or links, but oh well):
Ellen Kushner's Swordspoint is one of my all time favorite novels and another influence on My Heart to Joy at the Same Tone. Great book!
Any of Neil Gaiman's works, especially Sandman, which is my favorite comic of all time (yup, even beating any manga that I've read), and Stardust.
Any of Terry Pratchett's Discworld novels, cuz they're hilarious, smart, and fun.