Based on ncurses, MOC (music on console) is a popular, text-based audio player which can play various audio formats, including Ogg Vorbis, FLAC, MP3, MP4, WMA and WAV. The release I'm going to talk about in this article is 2.5.0-alpha3, as it comes with Debian Lenny.
By default, the interface consists of two panels, with a file browser to the left and the playlist to the right. You can start adding tracks to the playlist by navigating to a music directory and using the a key. To clear the playlist, use C (that's uppercase). Here are several useful keyboard shortcuts for using MOC (notice that uppercase and lowercase matters):
a add music files to the playlist
C clear the playlist
Right Arrow seek forward
Left Arrow seek backward
Space play/pause currently selected song
s stop playing
S shuffle playlist
R repeat playlist
Tab switch between panels
, increase volume by 5%
. decrease volume by 5%
Q quit mocp
? get help
MOC does not seem to include Last.fm song submission by default, but there is a script on the official website called lastfm-mocp, here (direct download link), which uses the Last.fm submission daemon (package lastfmsubmitd in Debian).
The configuration file for MOC is ~/.moc/config, but it is not needed by default. It also supports configurable keybindings.
MOC also supports various themes, which you can select by using T. To add more themes if the default ones are not enough, copy them inside the ~/.moc/themes/ directory. See several screenshots below:
I liked that MOC can also run as a 'server' by detaching the player using q. Overall, it is a pretty nice audio player for the shell, it's lightweight and provides a very good and easy to use alternative to other players like CMus or mp3blaster.