The war-book of the German medieval engineer Conrad Kyser offers a wealth of interesting and some crazy designs. 

This figure is taken from a page of Kyser's book, showing a fifteenth century "hand gonner" or hand gunner. These .77 caliber weapons were just starting to make their presence known on the battlefield, changing the character of warfare once more. 

This pin is good-sized, reproducing lots of detail. It's made from jewelers' brass, which reproduces detail beautifully, and it features a simple stick-pin style attachment point on the back, fitted with a friction cap to keep it in place.