Below are links to some of the best Dawn fics out there. Go read them, then send the authors nice e-mails telling them how great they are.
If you know of an exceptional Dawn fic which you think should be recommended here, e-mail us and let us know, but don't recommend your own fic. It's tacky.

Along Came A Spider, By Elizabeth - 1
PG-15, darkfic take on the Dawn, Spike friendship. Set after The Gift

Ambient, By Brighid - 1
R, a bittersweet Dawn/Spike futurefic. Set after The Gift

Anywhere But Here, By Harriet Spy - 1
PG-13, Dawn, Ethan friendship fic. G/E references. Set after The Gift

Arearea no Varua Ino, By Nepthys - 1
R Spike, Dawn Friendship fic. Set after The Gift.

College Girl, By Claire - 1
PG, Dawn/Tara fic. Set after Tabula Rasa

Common Ground, By Harriet Spy - 1
PG, Dawn, Giles friendship fic. Set during I Was Made To Love You

Dawn and the Dead, By HonorH - 1,2,3,4,5,6,7
G, Dawn in LA fic. Set after Forever

Diary, By Lady Jesca - 1
G, Dawn, Xander crushfic. Set after The Real Me

Don't Worry the Safety's On, By Prophecy Girl - 1
PG-15, just Dawn and a gun. Set after Wrecked

Ein Sof, By Kate Bolin - 1
G, an AU take on the mythology of the key. Set after No Place Like Home

Electric, By Bitch Willow - 1
PG-13, Dawn Introspection. Minor Spike/Dawn. Set after Blood Ties

Happily Ever After, By Mary Borsellino - 1
PG, how Season Five could have ended. Set during The Gift

Hard, By Claire - 1
PG-13, Dawn, Tara crushfic. Set after The Gift

Life After Buffy, By Saber ShadowKitten - 1,2,3,4,5,6
PG-13 Spike, Dawn Friendship fic. Set after The Gift.

Love: The Abnormally Weird Kind, By Pat Kelly - 1
PG-13, Buffy/Dawn angst. Set during Season Five, Forever through Tough Love

Pieces Of You, By Rebecca Parker - 1
G, Spike, Dawn friendship fic. B/R references. Set after The Gift

Puppy Love, By Flywoman - 1
PG-13, Dawn darkfic. References to a character consorting with a minor.

Runaway Trains at 3AM, By C.L. Kamnikar - 1, 2
PG, Dawn, Clark friendship fic. Crossover with Smallville. Spoilers up to Doublemeat Palace on BtVS and Hug on SV.

Something You Don't Know, By Shoshanna - 1
G, Spike, Dawn friendship fic. B/S. Set during Checkpoint with spoilers for Crush

Stone, Grass, By Twi - 1
G, angsty Dawn vignette. Set after The Gift

Test Subject, By Kate Bolin - 1
G, Dawn darkfic. Set after The Gift

The Momentum of Her Tears, By Ita - 1
G, angsty Dawn, Spike friendship fic. Set after The Gift

The Self-Same Lore, By Cynthia Liskow - 1
NC-17, Dawn/Other. Season Six from Dawn's POV.

Thursday Night Dinners, By Kate Bolin - 1
G, Dawn/Tara futurefic. Set after Smashed

Waiting With Strangers, By Ell - 1
PG-13, Dawn Pastfic. Set during Lie To Me

We Are Life, By Mary Borsellino - 1
G, Dawn, Spike friendship fic. Set after The Gift