Do Computers Consume Too Much?

I'm curious if anyone knows any details about the energy usage of average PCs in homes or businesses. Do PCs use less energy than, say, a television?

Some people are blaming the energy crisis in California on the digital economy. The driving force behind this economy is an increase in daily efficiency, but what about energy efficiency?

Shouldn't developments be undertaken to make PC and related hardware less taxing on our finite energy resources? Is anyone working on this?