好嘛啊

'drawdio' created by adafruit and jay silver is a pencil that lets you draw with the music. the kit is an analog 
synthesizer circuit that straps to any soft-leaded pencil, and lets you crank out electronic sounds while you 
sketch. using a single AAA battery for power the 'drawdio' works by taking advantage of the conductive 
properties of the graphite in pencil lead.