* LED, $0.04650 @ 1000: http://search.digikey.com/us/en/products/WP710A10SRD%2FD/754-1593-ND/2769819
* CD74HC164EE4-ND $ 0.30994 @ 100 :http://www.digikey.ch/product-detail/de/CD74HC164EE4/CD74HC164EE4-ND/1506713
* 74HC595N,112, $0.378 @ 100: http://search.digikey.com/us/en/products/74HC595N,112/568-1484-5-ND/763088
* CR2032 holder, $0.4968 @ 100: http://search.digikey.com/us/en/products/3003/3003K-ND/227448
* Pushbutton, $0.0916 @ 100: http://search.digikey.com/us/en/products/FSM4JH/450-1650-ND/1632536