Double Tap Defense has built a pocket pistol in .45 acp that eerily resembles the Liberator of WW2 French resistance fame.  The pistol does have many advantages over the original, and 60 years of firearm development since then didn't hurt.

Double Tap pistol

Dubbed the "Titanium Tactical Pocket Pistol", this gun has 2 barrels in .45 acp, fired sequentially, and in the event of a misfire has a double strike capability.  Like the original Liberator extra rounds are stored in the butt of the weapon, but are attached to a loading device that is stripped away when the cartridges are inserted into the chambers, quickly reloading the weapon.

Cutaway of Tactical Pistol

There are also several models to choose from.  The frame material can be aluminum or titanium, and the barrels can  be ported or unported, with the prices ranging from $500 to $800 bucks.  Extra barrels can be bought, and even available in 9mm.

Original Liberator

As something that could have been made in 1942 instead of the original Liberator, this pistol would have been a disappointment because it cost way too much.  The original cost about $1.50 to make in 1942 dollars, which would have made this pistol about fifty bucks back then, even if it was possible to build.  For that money you could have just dropped Thompsons and Grease Guns to the French (which we probably should have done anyway).  In the end, however, we lost the will to arm French civilians and dumped most of the Liberators in the ocean. 

Grease Gun

The proprietor of the excellent Wilkinson Fighting Knives Collection shared a  review on a commercial variant of the Webley MkI .455 automatic pistol.  These are pretty rare guns, and he includes a shooting review also.  You can find the review on this page.

The Webley MkI Autoloading Pistol