There was talk of an exhibit in the boys' rooms at the Children's
Discovery Museum of San Jose. It used a simple stroboscope (spinnable
disc with slits cut in it.) Just like the familiar strobe exhibit that
seemed to make a stream of droplets stand still, this would to the same
thing to... er... you know. I'm not sure how you could do a similar exhibit
for the girls' room.

Joe R.
Flandrau Science Center