The Wireless Sensor Network example from my Dreamforce 2013 DF13 DevZoneLab session. Yes, I will create a better Github at some point. Sorry.
Dreamforce 2013 Org Session Record: (registration required) https://dreamevent.my.salesforce.com/apex/ActivityList#a093000000XfGkBAAV
Slideshare with Step By Step instructions: http://www.slideshare.net/ReidCarlberg/diy-wireless-sensor-network-lab-at-dreamforce-2013
Salesforce Unmanaged Package: https://login.salesforce.com/packaging/installPackage.apexp?p0=04tE00000001XSU
Arduino Sketch: https://gist.github.com/ReidCarlberg/7393517
Node.js Gateway Server: https://gist.github.com/ReidCarlberg/7386924