Apple II History
The story of "the MOST personal computer"!
Computers: Prototypes
Apple II prototypes, some that never made it out the door.
Steve Jobs demonstrating Apple II proptotype, Apple Computer, (Stevens Creek), May 1977
Also, here is a video done by Joe Kohn, one of the people who first wrote about the Mark Twain (unreleased Apple IIGS model) when it was discovered in the 1990s: