Here's a list of 10 real, patented guy-inventions. The illustrations are the inventors' actual drawings, taken directly from the official paperwork filed with the US Patent and Trademark Office.

This is my personal favourite:

Albert's Helmet-Mounted Pistol (1953)
Why should we actually have to hold a weapon in our hand? We're guys. Our hands are too busy doing other guy things to be involved in a firefight. Our head isn't doing much. So, thought Albert, if I just strap a gigantic pistol to my melon I can keep my hands free for more important things. As Scott notes in the book, "Once this powerful weapon has been securely strapped to the noggin, a quick blow into the firing tube is all it takes to... send a large-caliber bullet rocketing in a generally forward direction." Not to mention cause severe whiplash and/or spinal injuries from the kickback of this monster.

Link - via digg