Here's the endearing story of an adult education teacher in California who blew off his hand when he tried to smash a bug with a 40mm artillery shell. Not only did he set it off accidentally, but he did it in front of a class of about 25 students.
Apparrently, he didn't know the shell was live when he found it on a hunting trip a number of years ago. So naturally, he brought it home to use as a paperweight.
Remember kids, don't play with unexploded artillery shells.