I've been rocking an iPod Video for like 15 years and it is still my go-to music device. All the stereos in my office, house and shop have a 3.5mm cable hanging from them.
I've also been using rockbox so I can play FLAC files. The ipod is on it's 4th battery at this point and I've also upgraded to SD cards from the internal HD about 6 years ago. The screen is not working in a few places now, but the thing keeps working and I'd be very sad if it ever stopped because I'm not sure what would replace it.
Whenever I'm programming and I feel like I've been very productive, it's often the times I'm using this ipod with headphones - instead of a music playing piece of software. Maybe it's because I'm less inclined to open up the software and spend time choosing an album/podcast/etc.