Good material for a standup comedy routine.
I'm getting a bit fed up with our local grocery stores treating me like a counterfeiter when I pay with a $50 or $100 dollar bill. All of the cashiers have those testing pens, and they all test every large bill that goes into their drawer. I find it offensive, myself, and may buy a pen of my own and subject their change to the same review, even down to the $1 bills, just to be an asshole about it.