One of my most delightful discoveries of the early 2000s was that iPod Minis used Microdrives that were pin-compatible with CompactFlash cards. I had a little cottage industry in the back of my office upgrading my coworkers’ old iPods to use bigger, solid state disks. I still have my 256GB iPod Mini. Aside from battery life, it still runs fine, and it is by far my favorite music player form factor.