Here's a good one.
My friend was outside at night with some friends near his garage and someone mentioned a cologne they were wearing. On impulse he grabbed the sprayer and spritzed himself around the neck and arms.
Problem is, it was this stuff...
Oooh he was cursing. "My skin is on FIRE!". We had a good laugh after determining it wasn't serious, and also noticed it didn't 'stop him in his tracks'.