retrocomputing

With 8-Bit-Wonders you can play both old and new pixel games in the style of the 80s while retaining all the advantages of your modern Android device (of course, other programs besides games also work)

Xcpc - Amstrad CPC emulator for Linux, BSD, Unix [this repository is a mirror]

https://www.xcpc-emulator.net/

PDP-11/40 (aka 11/35) emulator for various microcontrollers, some 11/45 stuff thrown in, but not enough for more than UnixV6 or similar age OSes.