beeper.exe
a pc speaker music editor made on a whim. it has built-in help, good luck!
http://aanaaanaaanaaana.net/code/beeper/16/BEEPER.EXE
there is also now beeper2mml - a java program that converts beeper.exe save files to mml files suitable for xpmck or ppmck:
http://aanaaanaaanaaana.net/code/beeper/16/beeper2mml.zip