I have been a big proponent of what I call "common sense green". I hate to see people do things for the sake of being green - but are not really green at all. Anyway I came across some useful information on the fine homebuilding blog regarding some green "myths". The article identifies a number of common strategies that do not necessarily save you much energy. Those include the following:
furnace tune ups
sizing furnace correctly (not oversizing)
basement duct sealing
floor insulation
caulking and weatherstripping
window replacements
tankless gas water heaters
cooling your attic
changing furnace filters monthly
opening your refrigerator quickly
using drapes to insulate windows
You should read the entire article if you want further information. See the following link: