The good old days! After using edlin to write BASIC on my parents' 80286, we got a Pentium with a modem, and I used it to download Ralf Brown's Interrupt List and an assembler. Both downloads, I started before I went to bed and they were done by morning. (So as not to tie up the phone line during daytime.) Rbinter wasy my guide to causing a whole new world of exciting crashy behavior. Ultimately I wrote a paint program in assembly before I gave in and started using high level languages like C.
oh the Turbo Pascal and Turbo C days, where I had embedded assembly code mostly to have fun with 5.25 drives. Did fun experiments with copy protection back then; it was a thing; down to interrupt handling and more.
also a fun way to seize up your computer when you got it wrong, I mean it compiled it should run, right?
[0]http://www.amazon.com/PC-Intern-Programming-Encyclopedia-Dev...