Fully documented source code for Elite on the BBC Micro
Hehe.<p>When I was about 12, I printed out the entire disassembly for the Disk version of Elite on the BBC, on a dot matrix printer.<p>Because dot matrix paper is continuous with perforations, the printout filled much of my room, and I pored over it, writing notes and getting to learn all the little tricks and algorithms!<p>So I had my own fully documented source code for Elite back in the day :-)