Hey Benjamin,
As a participant I can certainly say it was good fun, and I hope you'll have even more fun at CCC.
There is a remixed version of the Free Software Song by Avantasia, which at least seems to have a more conventional rhythm: https://soundcloud.com/theavantasia/free-software-song-remix Also it deviates in the lyrics somewhat. Perhaps you can take that as a base.
Best of luck! Nico