Linuxo Planet

beets is a cross-platform command line music tagger and organizer which you can use to "get your music collection right once and for all".

It can improve your music collection metadata by using MusicBrainz, download cover art for all your albums, reorganize your music files, fix filenames and more.

Further more, beets is extensible through plugins which add extra functionality like  embedding or extracting album art from files, fetch lyrics for all your songs, clean up tags and and there's even a HTML5 web player (though it's very basic and can't do too much for now).