For those who are interested in composing music using Haskell, I have initiated a page on the Haskell Wiki about projects related to Haskore: http://www.haskell.org/hawiki/Haskore I also like to point to my private work on Haskore. It includes bug-fixes, a more fine-grained modularization, better support for infinite music data, an automatic test-suite that is run by Darcs whenever one records a new patch, a Haddock reference documentation, some examples of music processing such as Markov chains. The Music datatype is now based on a more general type for temporal media as proposed by Paul Hudak. Unfortunately the simplicity required for teaching is partially lost. :-( The current state can be found at: http://cvs.haskell.org/darcs/haskore/src/ In the future it should support a more general notion of instruments and MIDI controllers. So there will be more incompatible changes ...