Free Software Song

The Free Software Song is a filk song by Richard M. Stallman about free software. The song is set to the melody of the Bulgarian "Sadi Moma".
A version of this song is also performed by a band (the GNU/Stallmans) during the credits of the documentary "Revolution OS". In 1998, Matt Loper recorded a techno version of the song. Jono Bacon also recorded a death metal version of the song, and the band Fenster recorded a rhythmic version. In addition, there is a Spanish pop punk version recorded by ALEC, and a Rick Astley mashup, "Never Gonna Give GNU Up".
A version is used in the free software karaoke video game Sinatra.
Lyrics.
The lyrics have been placed in the public domain.
Note: the audio-only recording on this page has slightly different lyrics, indicated in brackets below:
Additional verses.
In the spirit of free software, supporters are invited to write additional verses to the song.