It's not often that you die.
Dustin and his friends were out celebrating Dustin's birthday when an accident cuts the celebration short. Instead of the cold embrace of Death, Dustin feels the warm embrace of a pony. He wakes up to find himself in Ponyville with the body of a pony, and his friends missing. Twilight thinks there's a reason Dustin is here, but all He can worry about is finding his friends.
Dustin will have to not only rediscover himself, but also learn a lot of new things about himself. The ponies who were kind enough to help them are not without troubles either. Can Dustin single-hoofedly straighten not only his life out, but others as well?
Of course not, that's what friends are for.
(This obviously took some inspiration from 'One Way' a fic that I haven't gotten around to reading yet, but I'm sure is great.)