I have two - I was a safety coordinator for my previous job and I was having trouble with our maintenace dept putting acorn nuts back on the sides of the machines, this would cause our employees to catch their shirt on the exposed screws and either tear them or worse pop them open. In a safety meeting one day, I was fustrated about this and I asked the maintenance manager why he couldn't teach his guys to put their nuts on the machines when finished with them. The room got really silent on that one, before the laughter and my red face.