The moment the team arrived home in Ponyville, Fluttershy found herself pinned to the ground by Twilight.
"Tell me, Fluttershy, how does your tail do that?!" Twilight exclaimed, excitedly levitating a notebook and pen.
"Um, I kinda just... do it..."
"Come again?"
"It-- it just does."
Twilight cocked her head.
"What do you mean, 'it just does'?"
Fluttershy shrugged, lifting the ball with her tail to show Twilight.
"See? It just does it. I don't know how, or why it's possible, all I know is that my tail's strong."
"I know that, I mean, seriously, how can a bundle of hairs sticking out of a spine extension be so similar to a hand in function?" Twilight replied, earning a few sideways glances.
"Um, Twilight," Rainbow said, "you never really told us what a hand is when you came back through the portal..."
A few minutes later, as well as a certain pale unicorn artistic purposes, Twilight began to continue her mindless ranting.
"So, with such little muscle mass contained within most tails, that would mean that the tail must be assisted by an external for--"
Pinkie shoved her hoof in Twilight's mouth.
"Less, talky, more walky!" She exclaimed, pointing out the fact that aside from rarity, they'd only traveled a quarter of the way back to Twilight's castle... or really any of their homes...
"She's got a point, y'know," Applejack added, walking ahead of the group.
Fluttershy flew above the rest of them, humming a little tune to herself as she tended to some birds who had landed on her tail. Suddenly, her body jerked backwards as her tail whipped itself at the birds, scaring them off. Fluttershy screamed at the top of her lungs to see her tail suddenly take what seemed like a life of it's own.
"WHAT THE BUCK WAS THAT?!" Applejack shouted as she looked upwards.
Fluttershy continued struggling with her tail, of which was now thrashing about madly in the air, as if it were some wild beast.
Rainbow Dash zoomed towards Fluttershy to see what the matter was. Her eyes widened at Fluttershy's crazy tail.
"Hey Flutters," she called, "what's up with your tail?!"
Fluttershy landed the best she could, landing on her face from the tail refusing to sit on the dirty ground.
"Oof!"
Twilight turned to face Fluttershy.
"It seems almost as if her tail's... alive..." She murmured to herself, poking Fluttershy's tail with a twig.
The tail jerked once again, grabbing hold of the stick and flinging it at Twilight's face. Instinctively, Twilight ducked, casting a shield spell as she did so.
"Your tail's going wacko!" Pinkie shouted as she pointed at Fluttershy's enraged tail.
Fluttershy rolled her eyes, which her hiding behind her hooves.
"I know that Pinkie... but why does it have to be wacko?"
Pinkie, being the one who knows all, heard Fluttershy's soft voice over the sounds of flying dirt.
"Idunno!" She exclaimed, "It's just wacko!"
Twilight continued inspecting the tail, and suddenly plucked a strand of hair from it. Of course, this only made the tail even more enraged, going from kicking up dirt to hauling small rocks and flinging them.
"IGOTTAGONOWBYE!" Twilight suddenly shouted, disappearing with a flash of magic.
~~~{Two Minutes Later...}~~~
Fluttershy sat by the river bank, sighing grumpily as her tail splashed about in the calm waters. Twilight suddenly reappeared beside her, with a small mountain of papers.
"I found out why your tail's crazy!"
Simultaneously, all the ears of the mares perked up.
"POISON JOKE!"
Pinkie giggled nervously as she backed out of the area.
Author's Note
Just a little something I came up with based off the latest episode. 
Don't Eat Bean Cupcakes at Rave Parties.
Rarity's eyes glimmered in wonder. She had always gone to the "fancy" parties, with the tea-sipping and fedoras and such, but never before had she ever gone to a rave party.
"Do you like what you see?" Pinkie asked, bouncing up besides her friend.
Rarity stood speechless. The music, the lights, the ponies. She had never seen so many ponies in a single area, not even during royal gatherings.
"Pinkie," she said, turning to the pink mare, "why didn't you tell me earlier about these... rave parties?"
Pinkie rolled her eyes.
"Because I had to blindfold you, stuff you in a duffel bag, and pull you out in a closet to get you here?"
Rarity blushed.
"Um... yes, darling, I believe that I did put up quite a fit at first."
Pinkie nodded, folding her forelegs.
"Well, now that you're here, let's party!!!"
A heavily intoxicated Rarity stumbled her way towards the refreshment table, eyeing the large, puffy cupcakes that sat on the tray.
"CUPCAKES!" She hollered, grabbing the tray in her magic. She proceeded to begin snarfing each and every one of them down, making a very un-ladylike scene. All the while, her drunken mind decided to ignore the sight of a sign labeled "Bean Cupcakes" tumble to the dance floor.
"Enjoying the cupcakes, Rares?" Pinkie asked, trotting up beside Rarity.
"Ehuhuheh... yeah!"
"I knew you'd like them! You always said that you liked bean cupcakes!"
Rarity froze for a moment as her mind processed Pinkie's words.
"Beans... Cupcakes..." She gasped.
"Oh, Pinkie, I knew you'd make those lovely cream cupcakes I like!"
She bearhugged Pinkie, earning a few strange glances at the two, especially considering the fact that it looked like she was about to mount her friend.
Vinyl Scratch rubbed her chin with a hoof as she flipped through the long list of music. Suddenly, Pinkie popped up from inside the equipment cabinet, holding a cd.
"Here, play this!" She said enthusiastically, and disappeared into the cabinet once more.
Headbeating and dancing ensued as Rarity continued to swallow cupcakes with the ferocity of Kirby.
"Deez... deez here cupfakez... derr delisziousss!" She exclaimed happily, licking the plate.
"I know, right?! I put in red beans, mung beans, lima beans, baked beans, deez nutz, and vanilla beans into the batter!"
Pinkie held up an acorn, complete with the squirrel, which clung to the nut.
"SEE?!"
Above the crowd, Derpy was too busy headbanging to notice a bar supporting a portion of the ceiling. And because of it, she flew directly into the bar.
"Ow..." she said flatly, rubbing her head with a hoof.
Suddenly, the ceiling began to make a horrifically creepy groaning noise as it began to bend under strain. Vinyl cut off the music as she diverted her gaze up towards the failing ceiling, taking her sunglasses off for a better view.
"...Mother of--"
The ceiling caved in before she could finish.
Rarity woke up with a groan.
"Wha-what happened?"
All around, there were pile of drunken and/or unconscious ponies laid about. The building lay in ruins, but there was very little harm dealt to the ponies themselves, considering the fact that they're practically indestructible anyways...
HEY NARRATOR GUY, GET ON WITH THE STORY, OKAY?!
Fine, fine... sheesh.
Pinkie rocketed down from the sky, landing beside Rarity.
"How's your morning, Rares?"
Rarity groaned again, and rubbed her head.
"Ugh... I've got a terrible headache from last night... what happened?"
"What do you think happened?"
"Building collapsed?"
"Yep!"
Rarity thought for a moment.
"Lemme guess... Derpy."
"Yep!"
Suddenly, a very, very loud trumpeting noise was emitted by Rarity's behind.
"Oh my."
Author's Note
Deez nutz!
Also, drunk Rarity. 
