Knuckle Duster Revolver
This unusual gun is a 7-shot .22 caliber brass and steel revolver. It's tiny--the hole fits around a single finger. Gunmaker James Reid made fewer than 10,000 of them between 1865-1882, some of them in .32 and .41 calibers.
Link | Photo: curio96
http://homeplace-artsstuff.blogspot.com/2011/07/apache-pinfire-revolver.html
an even better knuckle duster