As a self-appointed, unofficial historian of General Magic lore (and former employee) I have quite a collection of Magic Cap devices. Photos of my complete collection are on my web site, and I'm posting the coolest of the prototypes here.
First: did you know the Sony PIC-1000 is not the first Magic Cap device? It's the first one that shipped, but in fact Sony created an earlier device called the HIX-300, code-named Bamboo. So what happened to it? Zarko Draganic told me:
Sony was always ahead of the game, and they were miles ahead of everybody when Bamboo was developed--it was definitely targeted to be a real product.... When it became obvious that the Magic Cap software was going to slip at least another year, Sony aborted the Bamboo product even though it was in pre production.