it's Advent time and I took the opportunity to program a song for you. The sound, i.e. speech synthesis and reverb, is rendered by the LLVM-JIT and the synthesizer is controlled via ALSA-MIDI by the Haskell live sequencer.
http://www.youtube.com/watch?v=0EQCgi5qa3E "Alta trinita beata"
You find additional information in the video description.