The SynPad uses four corner-mounted piezo sensors to determine the pressure and relative location of a given hit. The project can easily be made on the cheap, and turns out a pretty sophisticated Arduino-based MIDI percussion controller. Gang1ion shares the relevant steps and source code for making one yourself. [via Matrixsynth]
In the Maker Shed:
hahah, great comment.. yeah.. the picture does look crazy. Very cool video though! I love any arduino project that moves past the blinkenleds stage.