Rainbow Dash knows one thing for sure, she is definitely not a barbarous, uncivilized dolt who doesn't know polite conversation from a hippopotamus's rear end. And also that she's definitely not the one who's wrong. Rarity is wrong. Rainbow Dash is absolutely, totally, a hundred percent sure of it.

But then why did Rainbow just buy a wagon load of apology bouquets?

Twilight Sparkle is a gifted student and scholar. When she attempts to harness her creative side by writing a science-themed sensual romance novel, however, things rapidly get out of hoof. Can her friends stage an intervention before she humiliates herself (and them) at a prestigious literature recital?

No. No, they cannot.

This story is a sequel to Shipping and Handling

Magic is limited only by the strength of the mind and the passion of the heart.

After the events of "Shipping and Handling", young Dinky Doo sets off to begin her first term of study at the most prestigious magic school in Equestria, Celestia's Academy for Gifted Unicorns. The adventures that await her there will exceed even her wildest expectations, and a cast of colorful new characters will be by her side to share in them.

(This story is the sequel to "Shipping and Handling". It's highly recommended you read that one first!
Occurs during Season 3 of the show: After the Crystal Empire but before Alicorn Twilight.)

Steady Hoof is a skilled thief who has been driven out from his home in the Heartland to seek refuge in the City of Gardens and Cages. When his life is saved by a pegasus named Scootaloo, he is instantly smitten. But her life has been hard, and she has forsaken love. To win her over, Steady must brave the dark heart of the city and do the impossible: steal the Tyrant's heart.

Set in the same world as The Archer and The Smith

This story is a sequel to Hard Reset

After the events of Hard Reset Twilight's life and mental well being are slowly returning to normal. Her recovery is cut short, though, when a letter arrives informing her that the time loop spell she cast is causing severe damage to space and time itself. In over her head, Twilight tries to summon anypony who will know how to fix it. The pony she gets is the last one she ever thought she would meet... and nothing like she expected him to be.

Available in Spanish thanks to dgs1993
Series TV Tropes page

UPDATE: COMPLETE! You may have heard of Pipsqueak. He's a pinto colt, originally from Trottingham, saved Nightmare Night from being abolished seven odd years ago. Know the one I'm talking about? Yes? Good. Since then he's grown into a charming, cultured hedonist who wants to bed near every mare in Ponyville and a good few of the stallions. He has a slender build and some ponies say he has mares' hips, though he feels that those ponies should shut their bloody mouths. His best mate is the gregarious and multi-talented Featherweight, and his other best mate is the stoic trencherpony and excellent cook Chowder.

This is the story of a Friday, and the wee hours of a Saturday. It's a teacher training day, and Pipsqueak and his friends have no school.

In twenty-four hours, a sinister plot to take down a local business is launched, Snips and Snails dabble in the dark magic of Peyuase, a great deal of debauchery occurs, a cocktail of unrivaled destructive power is created and a small fleet of ships are launched! All of this and more, in Pipsqueak's Day Off!

Massive thanks to LittleSallyDigby for help, editing and advice.

Twilight isn't having a very good day. An experimental spell blew up in her face, an army of changelings is attacking Canterlot, and she just died. Yet somehow, it looks like it's going to keep going downhill from here.

Given the chance to correct what's gone wrong, Twilight swears she's going to fix all this even if it kills her. Which it will. Frequently.

Cover art by Pixel Prism
Spanish Translation
Series TV Tropes page

Twinkie Pie. Appledash. Rareshy. You know these pairings and may have favorites of your own. But what if every member of the Mane Six were paired with every other member in the same fanfic?! That's what the Combinatorics Project is--an epic treasury of fifteen ships spread across five parallel universes increasingly full of plot and whimsy. Can you guess which couple is which?
* The angster and her secret admirer
* The burlesque showmares
* The celebrity marriage
* The commune farmers
* The curse victim and caretaker
* The dessert caterers
* The hopeless homebodies
* The industrial mavens
* The mad scientists
* The masquerade hosts
* The model train overlords
* The multiversal adventurers
* The orchard grafters
* The rivals in love
* The weather aficionados
Plus: Twilight blows up like a balloon and goes out to 'have a spicy time'! Applejack and Rainbow Dash are competitive about everything! Rarity dresses like a butterfly--and later in five outfits at once! Pinkiezilla crushes a miniature town and argues with Octavia about her instrument! Fluttershy dances with an angel and keeps a weather diary! Derpy tells a six-word joke! Not everypony ends up happy, but most do! A little suspense is a good thing. Bitter sorrow! Transcendent joy! Probability cupcakes are cupcakes that cupcakes!
Note: This story was written during Season Two, so a few small things are out of date.

Rarity's exploits in "Sweet and Elite" set in motion a chain of events that will find the unicorn dressmaker taking part in the greatest airship race in the world, the Alicorn's Cup. Excitement will give way to terror, as Rarity soon finds herself the victim of a plot against Equestria, and shipwrecked far from home with her least favorite stallion, the boorish Prince Blueblood. Rarity will learn of treachery in Canterlot and abroad, and will have search for something of substance beneath the prince's obnoxious veneer as she struggles to not only save herself, but her entire nation.

Part One of Three
The Adamant Triskelion - Book One: The Flight of the Alicorn
The Adamant Triskelion - Book Two: The Abyssal Forge
The Adamant Triskelion - Book Three: ???

Bon Bon's voice is funny, and that's about all that anypony who meets her notices, as her marefriend Lyra soon steals the spotlight with her explosive personality, strange obsessions, and curious beliefs. And why not? Bon Bon is, after all, a perfectly ordinary, boring pony in every way but two: her voice, and the carefully kept secret that she isn't really a pony.

(Edit:) Now with an annotated version, courtesy of the incomparable Shoggoth Lord!