Freaking people out when you correct something they say concerning Marvel.
Idiot: She-Hulk is Hulk's sister
You: Actually, She-Hulk, otherwise known as Jennifer Walters, is Bruce's cousin. She was fatally wounded and needed a blood transfusion so Bruce gave her blood, and that gave her powers. Only, unlike Hulk, her green form is permanent and she retains her intelligence and emotions while she's She Hulk.
Idiot: *backs away slowly in fear*