From Squidder:

This actually came about as a happy little accident while trying to bend FLARToolkit to our will (tracking multiple instances of multiple symbols – a total pain in the ass. But that’s a story for another time). It just so happened that we were rocking out to Kiss’ “God Gave Rock & Roll To You” and it suddenly occurred to us that “Hey, it wouldn’t be so hard to make these things make sounds when they disappear.” So we did. And it was awesome.

We’ve (for once) posted a usable demo, so you too can rock out at your desk. Below is a quick video demo of all four sounds and after the break, you can see the demo of using multiple instances of the same drum.