An popular example of shipping in My Little Pony: Friendship is Magic, in which Twilight Sparkle and The Great and Powerful Trixie are paired together.
Its extremely high profile is due to its main proponent, Sethisto, running the central Friendship is Magic fansite, Equestria Daily.
"Twilight galloped away, tears welling in her eyes, running for the one pony whom she truly could trust. The door of Trixie's caravan slammed open, and the blue unicorn looked up in surprise; but a glance at Twilight's face explained everything. Without saying a word, she reached a hoof up to Twilight's neck and pulled her close. As the storm raged on outside, Twilight, at last, felt safe."
"Awesome story! I love Twixie!"