I've just been informed by a door-to-door salesman about this offer. It is for Victorian homes only. Based on what I gathered from the website, the Victorian Government is putting out an initiative to add these gadgets in your home to reduce green house gas.
Please let me know if you guys have had service from these guys. Thanks.
Similar to these, I think.
http://www.ozbargain.com.au/node/55258
http://www.ozbargain.com.au/node/58581