Insulation Rebate
The information I've found online about the federal government's insulation rebate programme is either written by vendors or incredibly complicated. The programme itself is actually quite simple, and I think it's one of the most important sustainability things this government is doing. It's cheap, it creates jobs and most importantly it's going to be very effective for years to come. Insulation isn't one of the sexy environmental things going, so just like energy efficiency it doesn't get much press.
The programme is quite simple: if your house (including rentals!) doesn't have insulation, you can get it paid for by the government. $1,600 should cover the cost of insulating most houses.
I've written a site that explains how the programme works and how to get the insulation installed using the government's subsidy.