Our boss walked in one day and my coworker was playing with a ball of mercury. He was batting it and rolling it around on the floor.
They wrote him up.
Early in the days of those curly fries florescent light bulbs, a woman in Maine dropped one and broke it. Like the packaging instructions directed, she called for the fire department to come for a clean up because of mercury.
The hazmat crew visit cost her over $2,000... beware of environmentalists seducing you with good intentions.