Moe Music 
Moe Music is a PHP-based database for music powered by MySQL. It allows users to add music to a database for use in a LAN party.
http://moemusic.sourceforge.net/EasyTAG Project
A GTK+ GUI program for quickly and easily editing info tags on MP3 music files.
http://easytag.sourceforge.net/
mbux - open source music box
mbux is a mp3 music box designed for use at public places. A "public place" can be your private party or a real public place like a bar or a pub. Just a place or time where do you giving others the opportunity to select music but without giving them the total control over the music playing software.
http://oswald.pages.de/mbux/
Ardour
A multichannel digital audio workstation for Linux.
http://ardour.org
