Okay, so I admit this is way off from the usual discussion found in this
group but I just couldn't pass it up.  A contributor to the web site
"Instructables" has posted directions to make an auto-playing harmonica
that uses a vacuum cleaner, a printer and of course a harmonica.  The
author provides enough information to give someone who is handy a chance
at building one for themselves.  It looks like a fun project, see
http://www.instructables.com/id/Episode-18-The-Self-Playing-Harmonica/

I see several opportunities for refinement.  The most important would be
to switch the air from blow to suck and off.  Next would probably be to
make it play MIDI files.

Bill Budenholzer