This morning I was walking through Lowes and saw they were selling DIY the Iris home security and energy monitoring solution based on Zigbee. See link: http://www.lowes.com/cd_Products_1337707661000_ (http://www.lowes.com/cd_Products_1337707661000_) I was very surprised to see how many accessories were offered at the retail store.
One thing to look at.
In the services tab on the site. Unless you are only wanting you do basic things and use the Basic Service. The Premium Service is $9.99 a month.
If you download some of the manuals from the site. You will also see ZWave modules. Maybe made special for Lowes' Iris line.
I have read that it uses a mixture of both ZWave and Zigbee devices. In a thread over on the CocoonTech Forums.