I loved the Atari 800 (also used an Atari ST and Apple IIe). I wrote a lot of BASIC and assembly language code, including some commercial apps. The Atari was astonishingly primitive by contemporary standards, of course, but it was a great way to learn about operating systems. I wrote 70 articles for home computing magazines, including an assembly language tutorial column for 2 years. That experience helped me transition from chemistry to my software engineering career and the 8 books I've written on software development. I'll always have a fondness for Ataris.