Neat things found online:
"Apache" Knuckleduster (folds into brass knucks)
Lignose Einhand (one handed cocking German pistol, copied briefly as a 9mm by Norinco)
"Rifleman's Assault Weapon" (a rifle mounted bowling ball sized satchel charge... forst read about this in a Jane's defense weekly in the '80s... wieghed like 16 pounds)
"Welrod" Silenced .45 (British issue commando arm, uses a 1911 mag but only loads 1 round at a time like the liberator.)
1896 Bergman Auto (looks like mal's pistol on Serenity, from the stepped barrel to the ring on the bottom of the magazine.)