Racquetball Modified to Jingle Bell using Liquid Nitrogen

A racquetball can be modified to ring like a jingle bell when chilled with liquid nitrogen.  First, attach a wire or string to the ball.  Next, cut an "X" into the ball and insert a glass marble into the ball.  At room temperature, the rubber is flexible and the jingle bell ball does not ring.  When the ball is cooled to liquid nitrogen temperature, the rubber cools to a glassy material (polymer chain mobility is decreased) and the jingle bell ball rings.  A movie of the demo has been posted to YouTube: https://www.youtube.com/watch?v=xfIm29nNo8g.  Happy Holidays!