I once worked on some piece of music, which are available on http://q37.info/download/music.
Content.m3u is a playlist containing all the music files.
fss.mp3 file is an arrangement (without the lyrics) I made from the Free Software Song.
All other pieces are personal compositions.
Some of the pieces were composed on an Amiga computer. They are easily recognizable by their style and how they sound. The other were composed using the MIDI technology, which allows to experiment various music style.
I'm not affiliated to the SACEM, nor to any organization of this type. If you wish to use this music, feel free to contact me. As Free Software developer, I'm also working on some tools to provide the source of this music, i.e. the partitions, probably in LilyPond format.