Best Alternative to Air-Conditioners?

window/central air conditioners are sucking up too much energy and costing me too much. Are there any feasible cheap alternatives? I've heard of evaporative cooling, over-the-roof sprinkler that sprays cold water to heat the metal roof/indoor connected heatsink, and other complicated plans such as fanning air through underground pipes (always cold), Which alternative do YOU recommend? I'm in the northeast zone 7. Thanks