Teaberry Organ
    This is the instrument that started it all for me: my first conceptual musical instrument.  This instrument was published in the book "From Mud to Music: Making and Enjoying Ceramic Musical Instruments" by Barry Hall. 
   
    An exerpt:  "This unique instrument generates no sound, can only be heard by the performer, and takes on new sound characteristics in different settings. To play it, you press your ear against one of the upper openings to hear that particular pitch. The sounds you hear are caused by ambient noise being channeled through the specific lengths of ceramic tube, whose resonances are tuned to a pentatonic scale.  The sound is similar to 'listening to the ocean' in a seashell.  Because the sound is dependent on its surroundings, no song played on the Teaberry Organ will sound the same in different settings.  The instrument got its name from a gum wrapper on which Jon sketched his original design."