A fan who goes by EthePianoMan on Youtube sent in a great parody/original pony video. As he put it, "I recently wrote a parody of a song by the band Jukebox the Ghost,
called 'Oh, Emily'. I rewrote the lyrics, taught myself the piano part,
and made a video of the new song, 'Oh, Pinkie Pie'." It is an impressive piece of fan music, and EthePianoMan did a really great job writing and performing it. Check it out!
(When I started on this post, an image immediately came to mind, but I couldn't draw it myself. Fortunately, the internet always comes through for me.)