"All right, I've been thinking. When life gives you lemons, don't make lemonade. Make life take the lemons back! Get mad! I don't want your damn lemons, what am I supposed to do with these? Demand to see life's manager! Make life rue the day it thought it could give Cave Johnson lemons! Do you know who I am? I'm the man who's gonna burn your house down! With the lemons! I'm gonna get my engineers to invent a combustible lemon that burns your house down!" ?Cave Johnson, Portal 2
Pour the juice of it into a sour, mean person's mouth. They wouldn't like it it because its so sour, realize that their attitude is similar to the sourness of a lemon and change to become sweet. :) Just something off the top of my head.