Have a Bad Day Day is today... isn't this just wonderful!?
As we began to research this day, we expected to find that this day was intended to recognize that everybody has a bad day once in a while.
Believe it or not, Have a Bad Day Day was created to encourage us to wish people to have a bad day. The intent is to have sales people stop saying to their customers "have a good day", and replace it with "have a bad day".
taken from http://www.holidayinsights.com/
I won't wish you to have a bad day though!!