When I first tried to answer this question I thought of talented makers whose output was small, men like Harvey Rodgers and Adolph Minar.
I thought about my own Holy Grail which would be Stewart Edward White's Wundhammer that he took to Africa. I have his other Wundhammer which might be more important in the scope of American custom makers.
I also thought about a few of the "fanciful" rifles that are thought to have been made like the Krag by Zischang.
In the end none of these were my recommendation. My pick was a rifle that in your lifetime you might only get to see a picture of one, if your lucky. They truly only come along once-in-a-lifetime.
