If old process nodes like that still exist, perhaps someone should periodically do a run of old chips which are getting scarce, like 6581s or fragile ASICs from vintage computers. I know people who grew up coding Z80 assembly on their home computers have fond memories of it, but there’s a glut of deadstock Z80s that won’t run out for a decade.

I’ve seen a VHDL implementation of the Z80 on the net. It is so old, it’s last fixes were from 19 years ago…