Here we have the second most famous prototype of all time. The Sony Mavica.
The US Army used a special version of the ProMavica MVC-5000 during the Gulf war to transmit images right out of the combat zone. The so called Digital Imaging Set.
Sony introduced the MiniDisc Data in 1993 (see memory cards section). Since Sony was always VERY fond of their own storage media
Video and still pictures on notebooks have always been difficult in the mid 1990s. Too expensive, excessive CPU consumption have caused notebooks to stand in the shadows of more powerful desktop solution.
Sony introduced the DSC-F2 in 1997 with 4MB internal memory and no memory card expansion slot. Comdex Fall '98 showed a prototype..
Sony published a 'Sony Open' edition for the 1999 Hawaii games..
The Sony Photo ID camera was shown alongside some other Photo ID systems at the PMA '99.
Among their 2000 portfolio there also was this Pen Cam.
Shown also on fairs like Intel Developer Forum 2000 Sony highlighted a small digital camera prototype
To promote their fairly new Memory Stick, Sony showcased some prototype digital cameras at Ceatec 2000 in Tokyo, Japan
In 2004 Sony announced the introduction of the Hi-MD, a Mini-Disc that could store 1GB of data