Back in 2006 Zeiss had the temerity to create an M-mount film camera that was everything a rangefinder should be and that worked and felt better than any equivalent Leica M, this was the Zeiss Ikon. But it had one big problem...
It had everything going for it as a high quality, practical, hands on photographer's camera. A big, bright viewfinder; a long effective base length rangefinder; easy loading film bay door mechanism; accurate centre weighted metering; short throw film wind on; ergonomic layout of controls including a lovely all in one control dial for ISO/ mode/compensation/shutter speed; light weight magnesium alloy construction; vertical running metal shutter for higher top shutter speed; plus a raft of other bits and pieces that all improved on known M deficiencies and it soon built up a sparkling reputation due to its exceptional build quality and especially its aforementioned bright viewfinder.
But, and it was a huge but, there was a problem. The problem the camera had was, for the serious Leica aficionados, it did not have Leica written anywhere on it. Nope the little red circle was nowhere to be seen. Maybe if it had had Contax written on it that might have been better, but I doubt it? Anyway though Zeiss owned, and stills owns, the Contax brand it was licensed at the time to Kyocera for use in their cameras like their Contax G2 etc. so they were unable to use it. Also the camera was made in Japan rather than Germany and that really didn't help it either. But amongst the true Leica worshippers, doom!
For the rest of us who loved film it was a high-quality much more practical alternative to a Leica M that was still fully compatible with all of our favourite M-mount lenses. ZI's were introduced at Photokina 2006 and discontinued after a short six years at the end of 2012 and I still have mine, one black and one silver, which I use to this day and they have never been bettered.
Now the funny thing is, since they have been discontinued, you try and find one in the used market on the dealers shelves, nope nary a one to be found anywhere. No one who has one seems willing to part with theirs, including many a (closet) Leica owner I suspect ;).