Peter the head engineer in the lab built a nice demonstration of wave motion in a multi-pendulum set-up where each pendulum has a different period leading to a 50s cycle. We are planning on building a larger demo which should reduce the frictional effects for the shorter period pendulums.
For a good write up on the physics behind this demo and how to make your own go to this link
A computer generated demo that helps you hear the patterns.
Congratulations to Sarah Thompson from the photon factory for getting into the finals of the 3min thesis competition.