There were lots of projects at Apple that never made it off the ground. When I was there in '88-'90 I remember seeing a few prototypes of their Mobius computer

There were lots of projects at Apple that never made it off the ground. When I was there in '88-'90 I remember seeing a few prototypes of their Mobius computer - an ARM-based system that emulated an Apple II much faster, and was (unfortunately) faster than a Mac II in native mode. It got canned before they ever got around to designing a case for it, but folks who had the prototypes kept them for quite a while.