You can do a lot of crazy things with fonts. Just off the top of my head:
Tetris Font - https://news.ycombinator.com/item?id=40737294
A font which is also an LLM - https://news.ycombinator.com/item?id=40766791
And in the same vein:
Tetris in a PDF - https://news.ycombinator.com/item?id=42645218
Doom in a PDF - https://news.ycombinator.com/item?id=42678754
next is to build a disassembled inside a pdf
get zmachine.ps and you could play zork i-iii, Tristam Island and tons of z3 zmachine games (search for calypso.z3 too) without cheating as the PDF format implements an ad-hoc JS interpreter where not all viewers parse it.
I made a syntax highlighting font (also mentioned as an inspiration to Z80 sans):
https://blog.glyphdrawing.club/font-with-built-in-syntax-hig...