This is a blog about the Safe Nail Gun. It is a nail gun that is created to prevent people from nailing their hands with pneumatic nailers. The gun has a capacitative sensor on it that can detect the electrical current that comes from the human hand. Once the current is detected, which takes literally milliseconds, the nail will no longer be fired because the air flow gets redirected and the piston will not release.
Note that this is an academic project for a group of business students at Boston University.