Hi again,
Here's the other post I mentioned in my "Mastermind" thread.
I've developed an application called "Glockencord", which is a combination of a glockenspiel and a harpsichord. When you tap the keyboard on the lower screen, hammers strike the glockenspiel on the top screen.
There's also an automatic mode that plays music defined in "Music rolls" (punched rolls of paper like those used in pianos and fairground organs) - well, an electronic version of them, anyway. A compiler is provided to allow you to produce your own music rolls from text files.
And there's more.... I've included some ready-made music rolls for you (7 of them at the time of writing).