Most recently I watched Rango which had a colt SAA-type gun with a swing-out cylinder. But there's more...the cylinder swung out the RIGHT side of the revolver.
I find this especially interesting because obviously some concept artist had to create the model for that gun, and then several different people no doubt had to work on rendering the 3D model for that thing. Before doing all that work, you think someone would, you know, look at a real gun, or know something about what a gun actually is. It would be like rendering a horse but with the knees bending the wrong way or something. It could be deliberate, but I can't imagine why.