[uncircle]

Here’s an idea that’s been following me for a while, if you like low-level stuff:

Make a toy OS that boots into a Lisp shell.

Another to appreciate how fast computers that we call old effectively are: write a game for the shell. Depending on your level of skill, you can try pong, snake, lunar lander, or a 3D software renderer.

[ValdikSS]

OLPC (one laptop per child) had Open Firmware, a Forth bootloader/firmware

https://lwn.net/Articles/209301/

[mghackerlady]

Open Firmware was originally a Sun thing, then Apple adopted it at some point as well

[fragmede]

Make something that makes music.