How To Make A Grappling Hook Gun With A Fire Extinguisher

After realising there were no instructions on the web to make a grappling hook gun, MIT student Christian Reed decided to invent his own and publish the instructions. Because nothing says “I love you, internets” like a good grappling hook gun.

Now I’m off to get a dry fire extinguisher. [Instructables via Hacked Gadgets via Make]