Leica film cameras.

Cameraquest has plenty of information about the rangefinder models, their particular quirks, their cons and pros.

http://www.cameraquest.com/classics.htm

When you get to the point about making a serious purchase, I recommend you give a strong think to the viewfinder magnification that would best suit your lenses and shooting style. The M3 is tops if a 50mm lens is the shortest you'll use, whereas the .58 viewfinder in some M6, M7 and MP bodies are best for wider lenses (down to 24mm), but not so good for the 50mm. For my style of shooting, the viewfinder framing is more important than the body model. Cameraquest has information regarding the viewfinder that many rangefinder purchasers don't consider, but should:

http://www.cameraquest.com/leica.htm

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