We know what you're thinking: This isn't a prison weapon, it's a chocolate bar. Actually, it's both! In order to weaponize a candy bar, an inmate needs only to heat it up (usually on an illegal hot plate). Once it's hot and melty, it can be thrown in the face of your enemies. This is particularly dangerous if the candy bar contains caramel, which doesn't come off easily.
Weapons made in prison come in all sizes, shapes and varieties! This weapon was constructed by a prisoner stuck in solitary confinement in Manitoba, Canada. He used a variety of items to create the weapon, including 10 toothbrushes, a pair of tongs, string and a lighter to make the bow. The darts were made from cotton swabs and aluminum foil.
This crude-looking pistol was made by welding together two tubes and just adding a handle to grip. To shoot the gun, the inmate would pack the barrels with the heads from matches and use small bits of metal as bullets. It couldn't have been very accurate, but it was almost certainly intimidating!