Back in the 80s/90s there were some questionable ports of TeX do unlikely hardware. Perhaps the most egregious of these was TeX running on a Cray supercomputer.

Back in the 80s/90s there were some questionable ports of TeX do unlikely hardware. Perhaps the most egregious of these was TeX running on a Cray supercomputer. Time on these machines was metered heavily. I can't imagine anyone actually used it for formatting papers. I had a dream of doing a hand port of TeX to 6502 assembly to see if I could get it running on a 128K Apple //e. I envisioned heavy use of bank switching to enable code to jump back and forth between the two 64KB banks which could only be switched in predefined blocks as I recall (the page 1/2 text/lores blocks, page 1/2 hires blocks, the high 16k and I think the low 48k that wasn't part of the lores/hires blocks but it's a long time since I played with that hardware.