NP - Whitney Music Box

[David Morris]

An early intuition about how to control total dynamics led me to
activate all graphic elements through a motion function that advances
each element differentially. For example, if one element were set to
move at a given rate, the next element might be moved at two times
that rate. Then the third would move at three times that rate and so
on. Each element would move at a different rate and in a different
direction within the field of action. So long as all elements obey a
rule of direction and rate, and none drifts aimlessly or randomly,
then pattern configurations form and reform. This is harmonic
resonance, and it echoes musical harmony, stated in explicit terms. I
tried this procedure in several films, and was gratified by the
consistency of the confirmation it demonstrated.
– John Whitney, "Digital Harmony", pp. 38

The link below has numerous Flash animations demonstrating Whitney's idea:

http://www.coverpop.com/whitney/index.php?var=v0