Jevons' Paradox, also known as the rebound effect, suggests that as things become more efficient, we use more of them, say building a bigger house or driving a bigger car as the fuel economy improves. I never thought it would apply in a world where energy keeps getting more expensive; I thought we would logically be using the greater efficiency to basically stay in the same place.
I was wrong.
Every week I see yet another way people are using wonderful technologies like LEDs to waste energy in new ways. This truck is doubly egregious; it not only is burning gas to generate electricity to run a three-sided billboard selling condos in Toronto, it is adding traffic to the streets, causing everyone else to burn more fuel. I don't know whether it sells any condos but if I was stuck behind it instead of on my bike, I wouldn't think much of Greenpark Homes.
See a great summary of the discussion about Jevons' Paradox at RMI Outlet.
How greater efficiency leads to greater waste, or how Jevons' Paradox clogs the roads
Another example of how we use smart technology to do such dumb things.