These days writing a command-line OS for 8-bit or 16-bit era computers is almost an old trick, but GNO/ME (any relation to GNOME is purely accidental) has the difference of both having Unix-like features like signals, pipes and multitasking, while also having been written back in the day, in the 90s. Author Jawald Bazyar shows it off here (26 minutes):
The story also includes a story of the author’s teenage dialup exploration, and stumbling upon a Unix system without a password on its root account, and other such young computing adventures.
GNO/ME can be obtained, for running in an emulator or on bare metal, here, if that’s your idea of a good time.
