What I used to do back in the '80s and '90s, before internet music streaming was a thing and before our computers had enough disk space to store our music colle

What I used to do back in the '80s and '90s, before internet music streaming was a thing and before our computers had enough disk space to store our music collections, was bring a CD case full of my CDs to work. I'd put on a CD and go to work on something. Unlike a timer going off the CD finishing wasn't really an interruption, but I would be aware of it enough to decide if should just put on another CD and keep going (which I could do well enough on autopilot to do without losing focus) or if I was actually near a good point to take a break. We did a lot of contract work writing firmware for hardware makers, and I was supposed to track how much time I spend on each project so we could bill appropriately. That fit in well with the CD system. I just had to put all the CDs I used while working on a given project into a pile for that project, and at the end of the day add up the runtimes of them all to get the time spent on that project.