I never did it often, but when I locked the keys in my car's hatchback back in the late 1980's in Denver I played the helpless female card. I had NO idea how to get the keys out so a nice employee of the grocery store broke into the car for me with a coat hanger. (My keys were in my purse at the time - in the back with the groceries.) After that I've always been extra, extra careful and never locked the keys in again.