Love changes relationships, though not to the point where they are no longer recognisable. Twilight loves to go flying with her marefriend, but sometimes... sometimes her marefriend can still be her teacher.

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Note: This story was written during Season Two, so a few small things are out of date.

Fluttershy remembers the kisses she'd shared over her lifetime, reflecting on the different circumstances and how she'd grown as a pony.

After a falling out with Diamond Tiara, Silver Spoon is befriended by Sweetie Belle. However as time goes by, the silver-maned filly quickly learns that she has slightly-more-than-platonic feelings for her new friend, and that some ponies aren't above petty revenge. Can Silver Spoon's new found feelings survive public humiliation, petty grudges, and potential rejection?

Cover Art and Chapter 9's art were commissions by angel-wing101, Final Chapter Art was a Commission by dragongirl983
If you use any without my or their permission, I will jump through the internet and murder you, so just ask first.

A long time ago, things were different under the Princesses. While Celestia tried her hardest to keep things running during the day, Luna indulged in her love of fillies all night, and eventually the conflict would cause one sister to be exiled while the other had to carry on alone for a thousand years. Even after the Princess of the Night returned, her sister had to explain to her that times had changed, and her indulgences were unhealthy and unacceptable.

It's springtime in Equestria and Twilight Sparkle and Princess Celestia find themselves out of sorts despite the gorgeous weather. Luna and Rarity both think they know the reason behind their moodiness and set out to make sure that true love blossoms - but will an unfortunate misunderstanding keep the two star-crossed lovers apart forever?

Illustration courtesy of nightmaremoonluna, adapted from a sketch by bri-sta.

Princess Celestia and Twilight Sparkle have a private meeting during the Royal Nightmare Night Party.

Sweetie Belle has a secret, that even her two friends Apple Bloom and Scootaloo don't know about. She likes to ship ponies. Two ponies in particular.