I don't think you can know Rarity without being at least a little bit scared of her. If you're not, then you don't really know Rarity.
This is the story of how she saved Ponyville one day.
Winner of the Make Rarity Not Garbage Barcast Contest. Preread by Pearple Prose, ScarletWeather, and Estee (who did nothing but stand in the corner in silence while I ranted at them about this story, but by God did that help).