In Classroom of the Future, Moondancer came inside a room where there was Cheerilee inside too. As you know, all mares living in post-Equestria Ponyland wear bows on their tails. Cheerilee, being an Equestrian-era mare, didn't wear one. What was the first thing Moondancer said to Cheerilee?
A bit meta, but it must be listed here for being excessively funny: In the end of chapter 47 of The Magnificent Six, there is an author's note involving Draggle and Reeka which says, "How they brainstormed, without brains, I have no idea."
In chapter 5 of Family Relics, while North Star and Firefly were thinking to find a place to stay, Firefly came up with the idea to ask a guard. Their place? Working as bunny waitresses in a casino.
Imagine Wind Whistler of all ponies turning into an air-headed Valley Girl in Tales of Dream Castle.