1. Sorry, didn't track who posted it: Street performance of "Ode to Joy". http://www.youtube.com/watch?v=kbJcQYVtZMo#!

2. Sorry, didn't track who posted it: Animated representation of prime factoring. http://www.datapointed.net/visualizations/math/factorization/animated-diagrams/

3. From ysabetwordsmith: Unusual version of magician's cup-and-balls routine. http://www.youtube.com/watch?v=FUv-Q6EgEFI