Infosthetics notes a idea to project how much energy a city is using on the plume of a coal power plant for all to see.
Electrimetric was created with the idea that if we know how much energy we use, and see feedback based on changes, we will reduce our resource consumption. The question is would this help because it reminds people how much energy they are using? or hurt because they see turning off their light is just a cigarette amongst the coal power plants pollution.
It seems like you could do this via a web page reporting how much energy your city is using, and I'm sure there are things like this out there. Avid readers, send those links in!