Hello. Some time ago i played http://www.kongregate.com/games/onimatrix/the-sandbox?acomplete=the+sandbox .
It's a game like The Powder Toy but not so big xD. There is a special element named "NOTE" It creates a sound : Beep.
The people from there made songs with this element , using the right delay. I think this would be very cool in The Powder Toy. We will can make car alarm ( if the glass is break? ) , police siren , maybe songs.
Unicorns