<p>At least 2 35mm cameras with interchangeable backs.<br>
1. The old Zeiss Contaflex, had a leaf shutter too.<br>
2. The rolleiflex 2002/3003, sort of a shrunken 6x6.<br>
There were all kinds of backs for the Nikon f. Polaroid, pin register, vacuum, and who know what else?<br>
Back in the old days there were all kinds of weird and wonderful cameras around. Panaramic cameras with rotating lens and a curved film plane, a sub 35mm TLR...</p>