Mp3blaster is an mp3 player for computers running a UNIX-like operating system, e.g. Linux, Free/Net/OpenBSD, etc. Its interface is entirely text based, thereby eliminating the need for a graphical environment like X-Windows.
Aqualung is a music player originally targeted at the GNU/Linux operating system, also running on Win32. It plays audio files from your filesystem and has the feature of inserting no gaps between adjacent tracks.
Exaile is a media player aiming to be similar to KDE's AmaroK, but for GTK+. It incorporates many of the cool things from AmaroK like automatic fetching of album art, handling of large libraries, lyrics fetching, artist/album information