There have to be some more designs that were so
elegant or well-done
that you stepped back to admire them.
What were they?
There are many 'little bits' of machines that I feel are well designed,
but nothing instantly springs to mind. An example is PDP11/45 floating
point processo, which automatically does multiplication by 1111 (say) as a
subtract, followed by shifts, followed by an add (thus turning it into
10000 - 1).
Oh, the RK07 head servo gets the honour for giving me many sleepless
nights trying to figure it out. I can;t rememebr how many signals appear
at the summing node of the output amplifier, but it's quite a few...
A software example is the firmware for the Z80 on the PERQ 2 EIO board.
There's a cooperative multitasker hidden in that ROM.
-tony