You know what the Mojave desert was missing? My Little Pony, of course. My Little Pony buddies, to be precise. Here's a mod by Kuroitsune and Riven1978 on New Vegas Nexus that allows you to have the MLP protagonists as your companions.
Not all ponies are included — for now, there's only Luna, Celestria, Twilight, Fluttershy, Applejack, Rarity, Rainbow Dash, Pinkie Pie, Ditzy/Derpy and a few others. Perhaps the best part about this is that the ponies come with specific perks.
Littlepip - Stable 2 - Whenever Littlepip is your Pony Companion, you will receive +10 points to Science, Medicine, and Repair and 1 point to Charisma, at a cost of 1 point of Agility and Strength, and -5 to Guns, Melee Weapons, and Unarmed Weapons.
Luna - Mare of the Moon - During the night as long as Luna is your Pony Companion, you will slowly regenerate health. Luna will also gain a 20% combat effectiveness.
Celestia - Mare of the Sun - During the day as long as Celestia is your Pony Companion, you will receive 30 points to Energy Weapons, at a cost of 10 to all of your other offensive skills. Celestia also gains a 20% damage potential.
BonBon - Friendship Is Magic - When Bon Bon's health gets below 30%, Lyra will appear to help out in the battle.
Lyra - Friendship Is Magic - When Lyra's health gets below 30%, Bon Bon will appear to help out in the battle.
Twilight - Studious - Twilight's intelligence is par none. While she is your Pony Companion, your accuracy, spread, and critical chance improve by 20%.
Fluttershy - All Creatures Great and Small - While Fluttershy is your Pony Companion, every creature in the Mojave is your friend, at the cost of your human relationships.
AppleJack - Apple Cider - While Applejack is your Pony Companion, she will give you Apple Cider every time you give her 2 Apples.
Rarity - Rarity & Charity - While Rarity is your Pony Companion, you will find more caps or hard to find weapons on fallen foes only she kills.
Rainbow Dash - Speedy Arrival - While Rainbow Dash is your Pony Companion, you will be 10% faster at everything you do, at the cost of 30lbs of your total carry weight.
Pinkie Pie - Party Time! - While Pinkie Pie is your Pony Companion, you will find more chems on your fallen enemies. But you will be 20% more likely to become addicted to chems.
Derpy - Muffins! - While Derpy is your Pony Companion, she will give you 3 Muffins every time you use a campfire once a day.
Trixie - Trixie's Greatness - While Trixie is your Pony Companion, you gain +10 to all of your skills that are under 50 skill points.
Vinyl Scratch - Bass Cannon - Whenever Vinyl Scratch is your Pony Companion, any explosive based weapon you use will have three times the power, at a cost of -20 of your sneak skill.
You can download it here, though I'm a little sad that they walk upright. I mean, that kind of makes it more hilarious, but still!
My Little Pony Follower [New Vegas]