These musical hand puppets by Matthew Irvine Brown look irresistibly fun to play with. Sensors in the puppets mouth measure how wide it's open and that data is converted to a musical scale. They can be tuned to sing in any scale or mode. At the minute their voices come from a small Max/MSP patch and some very basic electronics, but he can also be rigged up to be a MIDI controller.

They can help illustrate relatively complex musical theory - such as the differences between blues, chromatic and pentatonic scales - through play and storytelling.

[Via Make]