I saw mention of the upcoming "Moogfest" in Durham, NC later this month. Browsing the festival’s website, this caught my eye: The Counterpointer, described as “a cross between an electronic arpeggiator and a baroque music rule book. It takes a melody input and responds with voices that follow the rules of counterpoint.”
See a demonstration of The Counterpointer here. (I wonder how many users know what that cantus firmus button is all about.)