Doorlock remote with bluetooth and an arduino

I like the build and idea, but…This could be done on such a cheaper scale.  Thought the Bluetooth module is the low-power version of Bluetooth.  The Arduino will still sip electric.

http://makezine.com/projects/controlling-a-lock-with-an-arudino-and-bluetooth-le/?utm_source=feedburner&utm_medium=%24%7Bfeed%7D&utm_campaign=Feed%3A+%24%7Bmakezineonline%7D+%28%24%7BMAKE%7D%29&utm_content=%24%7BGoogleReader%7D