throw7638: I had a fraternity brother who was a real jerk to me in college and hazed the crap out of me. Back then, you could log into the registration system to sign up for classes.
He was a senior, so he got the first pick of the classes he wanted. This was right when the internet was becoming popular, and back then, a person’s login was their name, and their pin was their birthday. I logged into his account and dropped all of his classes three days after they started.
He did not find out until midterms when the professors submitted his grades. They refunded his money, but he had to spend an extra semester in college.