It’s a great piece of engineering. Kind of along the Unix philosophy in that it does one thing, and it does it extremely well. 
Let me add my experiences here by repeating what I just wrote in another thread:
When it comes to sound I highly doubt any portable player can seriously beat the Sansa Clip+ (or the Fuze), at least not after it’s rockboxed. I have been using an ancient player until I bought that Clip+, and the main reason was that I was never quite satisfied with the sound of newer players; either it was just flat (iRivers, iPod Classic) or highly adjusted even with a “0”-EQ-setting without offering serious settings (peak-EQs or none at all, Cowon, iPod Shuffle), so I used my player for more than five years (a →Pontis SP600, very good sound, extremely durable, almost no functions and a maximum of 4GB storage, though).
The most important thing for me has always been sound. I came across the Clip+ while browsing various headphone-forums (head-fi.org and the like) where it was often recommended despite its low price. I use it with an →AKG K142 HD (because it’s one of the better headphones that can be easily driven without using an extra preamp) and really: sometimes it feels like someone is pouring sweet cream inside my ear.
Sansa clip is really the best out there. The good thing here is if you look at the box it says linux compatible.
and I like the oggvorbis format than the mp3 that this tiny piece is supporting.