Rollei 35 S
The Rollei 35 was released at the Photokina trade show in 1966 as the world's smallest 35 mm film camera. It has the size of about 2 1/2 film boxes. In order to achieve this tiny size, it has a rather quirky design with the film frame counter, rewind crank and flash hot shoe on the bottom of the camera. It has a viewfinder but no rangefinder: one has to guess the subject distance and set the focusing ring accordingly. Though with the help of an easy-to-read depth-of-field scale, it's not too difficult to dial in an appropriate focus setting. Often that will just be the hyper-focal distance.
The original Rollei 35 came with a 40 mm f/3.5 Tessar lens. A lower cost, plastic body "B" model followed in 1969. In 1974, the 35 S model was released with a f/2.8 Sonnar lens. At that time the old 35 model was renamed to 35 T (for "Tessar" lens). In 1980, the 35 TE and SE replaced the older models.
More than 2.5 million of these cameras have been built in total. At first in Germany and then, starting in 1972, in the Rollei factory in Singapore.
I have the limited edition 35 S Silver model. From multiple (slightly diverging) sources on the Web, I gathered this must have been built around 1979 in commemoration of the 1 millionth 35 S produced. And the laurel wreath next to the camera name indicates it was one of 3000 silver edition cameras meant for export to the US.
Invented by Heinz Waaske
The concept for the camera and all its design details came from German precision mechanic Heinz Waaske. He developed his idea starting in 1962 as a secret side project while still working for the Wirgin company in Wiesbaden, Germany. There he had designed the very successful Edixa line of SLRs in the mid-1950s. That was the first 35mm SLR camera with focal plane shutter made in West Germany. With its affordable price, it competed successfully against the East German Exakta and Praktica cameras. But Henry Wirgin, the owner of the Wirgin company, was in no mood to take on the risk of this entirely new camera concept and rejected the idea.
So Heinz Waaske left Wirgin in 1965 and joined Rollei in Braunschweig, Germany. That was after he unsuccessfully offered his camera design to Leitz, Kodak, Voigtländer and Agfa.
Rollei, on the other hand, trying to move on from its declining twin lens reflex camera business, enthusiastically supported the idea for this miniature-size 35mm camera. It came to market in 1966 as the Rollei 35. After the success of this camera, Heinz Waaske later also designed the world's smallest 110 film ("instamatic") camera: the Rollei A110.
Using the 35 S
The camera is fully mechanical, though it has a battery operated light meter with a needle display indicating the resulting exposure (based on the chosen aperture value and shutter speed). Because the light meter is on all the time, the black leatherette soft case is an important part of the camera as it will cover the metering sensor and prevent battery drain. The sensor is on the front face of the camera, covering the same field of view as the lens.
The camera expects a now banned PX 625 mercury battery to operate the light meter. I think the best option is to either not use the meter, or get an adapter that will take a 1.5 V silver oxide battery and convert its voltage to the 1.35 V that the original mercury battery would have provided.
To load film, the whole bottom half of the camera comes off and uncovers a somewhat unconventional film transport mechanism. It results in the photos appearing upside down on the film (relative to the pre-exposed frame numbers).
The lens barrel recedes into the camera body. Once it is extended and a photo is taken, it can only be retracted back into the camera body after the film is transported to the next frame and the shutter is cocked. That can get slightly irritating when the last frame of the film is exposed and the film can't be advanced anymore. That means that the lens also cannot be retracted back into the body at that point.
Because the camera is so small, it is easy to carry along as a second or third camera, perhaps loaded with some specialty film. In my case, I have used it occasionally for color infrared film.
And on a trip to India, it made for a very light weight travel companion that I could slip into the pockets of my hiking pants.
I have gathered most the information provided here from the (German language) book "Kameras für Millionen". It is a biography of Heinz Waaske by the authors Jörg Eikmann and Ulrich Vogt and was published by Wittig Fachbuch. A very interesting read with a lot more detail than what I could summarize here.