I was working at Apple when that particular model Mac was being developed. Those of us with no need-to-know got odd prototypes that looked more like a steel ammo box with bundle of cables coming out the back — tethered to a display that you had to prop up (some people might have got a kind of simple stand for the display).

In any event, the elaborate arm mechanism, dome plastics we would not know until the model was unveiled to the world at whatever the event was.

Before that though, the steel box didn't stop us from opening it up to look inside. Though our steel enclosures had something closer to a baseball "home plate" footprint, when we peeked inside we saw the circular PCB and knew we were being duped.

With the dangly display they seemed to go quicker than other prototypes to the dumpsters left in Apple's hallways when the actual product was released. I am aware of three MAME machines I built around discarded prototypes. (Shhh!!!!)

I think two of the three prototypes running MAME died eventually — the third I left behind at Apple when I retired. So, fate unknown.

Shortly after though is probably when Apple started locking the dumpsters to keep out the divers like me. (Well, probably more to keep them from ending up on eBay I suspect.)