I remember them days.
They were days in solitude, but cool nonetheless.
I remember when a kid on my school bus gave me the first cracked c64 disk of 5 or 6 games, I know donkey kong was one of them. looking at the dir of the disk, it looked like they just somehow copied the hunk of data from the cartridges... anyway, it was fun figuring out how it all worked. I went from saving out sprite data to disk - and writing BASIC routines to grab certain sprites from disk. Then I wrote my own routine for rewriting characters.
Compute!'s Gazette published MLX, which allowed you to enter machine language programs and save them. I learned some assembly after that... Now that I think of it, those were my most developmental days as far as computers were concerned...
When I finally had an A500, I started to get familiar with C.