I've just uploaded to hackage a step-based music sequencer, called "hbeat". It's little more than a toy, but it's fun. It ought to be cross platform, though has been built and tested solely on linux. Given that it's only 400 or so lines, it may be a useful example for anyone wanting to combine OpenGL graphics, interaction, and sound via the SDL libraries. It's also interesting that more than half of the code is "pure" (ie outside the IO monad), despite the fact that this is a stateful app with real time interaction with the real world. Further details here: http://dockerz.net/software/hbeat.html Thanks to lemmih for the SDL bindings that made this possible. Tim