I found the first video tonight and watched it, kids in tow.  They loved it as much as I did, and we spent the better part of an hour watching the others found below.  Enjoy!

Violin, synced to game

Beatboxing Flute

A capella

A ruler

Two Tesla Coils

An ocarina

A really sick drum set

Stepper motors

A radio controlled toy car and a bunch of beer bottles

A cell phone