I was removing a square drive allen wrench from a socket. It had been stuck for some time, so I resorted to clamping the allen wrench in the vise and clamping the socket with a good set of Vise Grip pliers. As soon as the socket came free from the allen wrench, it flew up from the upward pressure I was applying and smacked me right in the bridge of my nose. In this case neither the allen wrench, vise or Vise Grips were dangerous, the process of separating the two was the culprit. Keep it safe.