Spent some time replacing the battery and upgrading the storage on my 15-year-old iPod Video. From a 30GB disk to 256GB microSD, everything was plug-and-play, and the only tool I needed was a guitar pick. The SD card plays nice with Rockbox firmware, too (as far as I can tell).
I have an original Zune buried somewhere around here that I want to put an SSD into. The FM radio, with switchable US/European band plan, is a real plus for me.
I picked it up off a "free to good home" shelf a few years back. When I tried to do something with it, I found it wasn't really possible under Linux, but now ― although or perhaps because Microsoft has ended support ― the hacker/hobbyist support is better. So now I have to figure out where I put it!
"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko