Twilight wakes up with a serious head-ache caused by her horn spontaneously growing due to a sudden increase in her magical power. Nopony seems to have an answer for it, but it has attracted the attention of an unusually powerful militant foreign nation intent on her capture and execution. When a string of events lands Twilight before Celestia's father himself he tasks her and her newfound magic with tying up some loose ends he'd left behind long ago, ultimately connecting with this foreign nation's goals. With their powerful enemy baring down on Equestria, intent on taking it in a stranglehold, Twilight and her friends have little other choice than to travel the world and hunt for the rest of Celestia's family and end several thousands of years worth of feuding to prevent the war coming to Equestria before they themselves are caught.

Image Picture by Lostzilla of DeviantArt.
(find him yourselves)

Ech is a whiny bitch, but he helped edit a little I guess. (you too bats)

It is the year 2038, and the Earth is slowly being consumed by a space-borne monstrosity dubbed the Black Tide, which is using nanotechnology to remake the planet into something hideously alien.

Erin Olsen works for Project Harmonics, humanity's last-ditch effort to find a new world before the Tide can wipe them out. But when that world is found, and it turns out to be occupied, Erin will need to find the courage to face the unknown in order to save the inhabitants of both worlds.

(Many thanks to Easteu for the fantastic cover image for this story!)

Now with its own TV Tropes page

There is now a follow-up to this story: Sunflower - Side Projects
Sequel: Project Sunflower: Harmony

Every rising star must eventually fall. Rainbow Dash is locked in a struggle against her own past, and with the help of Twilight is about to make a discovery that will change the way she flies forever. But what will she lose in the process?

Massive thanks to Furor1 and Nyuuchandiannepie for the ridiculously awesome artwork, you should really check them out on DeviantArt if you've not already.

Dedicated to Donald Campbell and his Bluebird, for chasing his horizons for no other reason than the fact that they were there. Also to Steve Hogarth and Marillion for writing Out Of This World, the song that inspired this story.

Humans.

Truth or myth? Ancient lost civilization or just an old pony's tale?

No pony has ever seen one, and most haven't even heard of them. But Lyra knows that these wonderful creatures are more than just old legends, and she's going to find out... and possibly drive her roommate insane in the process.

Twilight is invited to Canterlot to compete with some of the greatest magicians in the world for the Moonstone Cup, a prestigious award for the most powerful and skillful magicians, unicorn and otherwise. Can she win? What sort of competition will she face?

Awesome cover image was taken from NoOneBahtim

Hope is the faith of the young. Losing everything she holds dear, Puppysmiles embarks on the adventure of her life to find her mother, her hopes of meeting her again driving her through the horrors of a world not of her making. Too bad the Wastelands doesn't care about hope.

A short trip to Canterlot with Rainbow Dash and Applejack is the perfect opportunity for Twilight to test out her new long-distance Teleportation spell. But a nasty cold dashes the hopes of a quick trip, and makes the spell disappear in smoke: instead of arriving in Canterlot, the three find themselves in the nearby Everfree Forest, and discover that their location is not the only thing that went wrong.

While Rainbow has exchanged her wings and tail for a straw blond tail, Applejack has acquired a rainbow tail as well as a pair of strong, blue wings.

While Twilight attempts to find a spell to return the body parts to their rightful owners, the others must attempt to deal with this situation... and with their changing feelings.

A horrible Cataclysm has turned all of Equestria into a Wasteland of barren ash and twilight desolation. The Sun and the Moon have been destroyed. Everypony has died--including Princesses Luna and Celestia. But one pony miraculously survives; she is a lone wanderer, the last of her kind, surrounded by menacing creatures that hate her. She navigates the Wastes in an airship and scavenges off the blighted landscape to keep herself alive.

Then one day she meets an old companion who grants her a gift, the chance to go back in time to the warm and sunny days of Ponyville, where her dead friends live in happiness. How far will the last pony venture into this joyous age of Equestria, even if she fully knows that there is no way to change the horrible fate of everypony she loves?

2013 Edition: Smaller Chapters, Better Grammar, and a Few New Scenes

(A shout-out to Vimbert, pre-reader and gentlecolt)

Twilight and her five friends are transported during a botched spell, across dimensions to... Ponyville, Equestria? But not the same one that they knew. Sitting on a bench is Harpsy and Babar. The Doctoress avoids apples from an aspiring Applebuck. And in a library across town, six stallions join their forces as they try to decipher the appearance of filly look-alikes of themselves around Ponyville!

Luna discovers something hidden from Celestia for twenty years, now, with emotions running high, she enlists the help of the Mane 6... but what seemed to be a single mystery, soon reveals a darker and much more complicated plot that will soon decide the fate of Equestria.

Check out the Empty Room TV Tropes Page (Warning: Spoilers!)

Revised chapters edits and proofing (with many thanks) by: lammy, Trevor, Nick Nack, Fifth Alicorn