Here is an improvised projectile for your favourite shotty.... It may not be a reliable man stopper, but it will require one hell of a band-aid to cover the impact injury if it connects.
Take 2 1/4 oz lead sinkers and cinch a 12" 100 pound test steel cable between the two and load in your shot wad, takes out power lines, rigging, and limbs, and will take a deer's head off, trust me, you don't wanna get hit with one!