I almost got kicked out of school for this! I sent an email to my girlfriend from some girl that we didn't like, saying something like "you're a huge bitch, haha just kidding this is actually jballs not the chick we don't like."

Problem is that I wrote my girlfriend's email address wrong, so it bounced back to the sender (the girl we didn't like).

So I had to explain to a university dean exactly what I did and how I didn't actually "hack into" the girl's email account. That was fun.