High tones are played through a salt/grit covered steel plate,or a bowl of cornflour.
As the pitch changes the sound vibrations arrange the salt/grit/cornflour into complex geometric patterns.
salt
http://www.youtube.com/watch?v=GtiSCBXb ... re=related
cornflour
http://www.youtube.com/watch?v=UU7iuJ98 ... re=related
grit
http://www.youtube.com/watch?v=YedgubRZ ... re=related