In 12th grade at my high school, we sat outside for lunch. Two of the guys at our table forgot to bring index cards for a class that was later that day. They really needed to have some, so one of them goes inside the cafeteria and asks everyone if they have any extra. While he was doing that, another guy at the table finds a whole pack that he doesn't need or want. So when he gets back, I ask him if I could see the index cards and I rip them in half right in front of him. For a second, he was in horror and anger and got some karma as he punched me in the arm. I then revealed the index cards we had saved for him, and then he just felt stupid.