I use a Sansa Fuze music player that I’m quite happy with. It supports the USB Mass Storage protocol and thus can be used (and filled with music) just as any other USB flash drive. This means it is fully supported by all operating systems since it doesn’t need proprietary software running on a PC.
However there’s one thing that tools such as Windows Media Player or iTunes are capable of that might be quite useful: managing playlists on the computer and transferring them to the media player. I accidentally found out recently that this can be achieved with Rhythmbox, the music player that comes with Ubuntu and other GNU/Linux distributions:
- connect player to computer (tested with Sansa Vuze, MSC mode)
- fire up Rhythmbox
- left column: under “Devices”, right click on your player
- choose “New Playlist”
- enter a name for the playlist
- drag music files from the player onto the newly created playlist
- safely remove the player when done
Effect: A new .m3u file is created at the root directory of the player, containing the playlist. It now appears in the list of playlists of your player (Music -> Playlists).