Meanest April Fool's joke of all time: When we were in college, my now-wife and I knew the combinations for the other's mail box. One day she checked my mail and called me to let me know that the law school application, for the law school I most wanted to attend, had been returned due to insufficient postage. I panicked, as the date for submitting application had passed by that time. I thought I wasn't going to be able to go to the school I most wanted to go to as a result of insufficient postage. I was really upset. She actually let it go on for a while before yelling "April Fools." It was really evil.
She has pulled similar "funny" April Fools jokes since. She even did the same one two years in a row, and got me both times. The combination of not being too bright, and never thinking of April Fools, made me an easy target, so I think she got bored with it after a while (ten or fifteen years).
