Information Aesthetics (a great blog by the way) has an interesting post on insulation. There's a high activation energy for people to determine whether or not they have appropriate insulation. Either you need to climb around in your attic and have a practiced eye and know about R values of insulation, construction and so on, or you have to pay an expensive consultant. But here's a way a group quickly and cheaply (spread across everybody's energy savings) found a way to get past that activation energy.
"Out of most existing buildings, a significant amount of heat escapes unnecessarily, out of which at least 30% is typically emitted through the roof construction. Many governments throughout the world attempt to tackle this problem by supporting the insulation of roofs through rebates, tax credits and other financial incentives. But how can individual citizens determine whether such a costly renovation is worthwhile for their own house? The online project 'Zoom into Your Roof' [antwerpen.be] tries to help solve this question through a relatively simple visualization. During the winter of 2009, a small airplane with an infrared scanner made a wide sweeping thermal scan of a large part of Belgium, which resulted in the largest thermographic map currently available online. Inhabitants living within this area are able to select their home address and answer a few questions (such as the angle of the roof). in order to determine for themselves how their own roofs actually perform."