Although Prince of Persia was the source of inspiration, my first real engagement with a computer happened around 1991 on a DOS box that was running Wordstar - a no-frills, no-mouse word-processor. I think I typed a small prose on it off of a book. It was thrilling to see English letters appearing magically in 8-bit flashes of light on a blank screen in front of me.
Turns out that George R. R. Martin wrote (and still writes) his seminal works on Wordstar!