* Pushbutton, $0.0916 @ 100: http://search.digikey.com/us/en/products/FSM4JH/450-1650-ND/1632536
* Pot, $0.3197 @ 100: http://search.digikey.com/us/en/products/3306P-1-105/3306P-105-ND/84994
* Jumper, $0.04516 @ 500: http://search.digikey.com/us/en/products/NPC02SXON-RC/S9341-ND/2618266
* PCB 5cm x 10cm, $1.498 @ 50: http://www.seeedstudio.com/depot/fusion-pcb-service-p-835.html