Environmentally friendly PCs, a new trend for 2008?

Not too long ago the pinnacle of gaming bliss was a dual core AMD PC outfitted with two Nvidia graphics cards in a SLI configuration, obviously sporting a RAID0 configuration of the fastest 10K rpm desktop drives and a barrage of case fans to keep all these hot components running cool. To state that the power requirements of such a system were rather steep would be an understatement as a +500W power supply was a stringent requirement and usually barely able to keep pace. Obviously the impact on your annual electricity bill for running such a PC on a daily basis would be substantial, or from an environmentalist point of view the equivalent of a hard smack across the face..