Slin,
my apologies go drifting a little off topic here, but check this out...

http://www.youtube.com/watch?v=0h-RhyopUmc&feature=related

Think on this... How cool would it be if you could use AckR to simulate the 'reactable' concept?
You could use the AckR symbols on bits of cardboard to schieve
the same results if we can get A7 to reproduce the sounds...

Off-topic complete...

[EDIT] Once I find where Ive hidden my webcam Im gunna have a play...