The Coding Horror blog
set out to discover the answer. Of course, you’ll need a way to figure out how much juice your computer is using up, which will either require you shell out a few bucks for a measuring device such as the
Kill-a-Watt, pictured above (a useful gadget in and of itself). You convert that into kilowatt-hours by multiplying it by the amount of hours you leave your machine on, then use your power company’s cost per killowatt-hour, and voilà! That’s how much it’s costing you.
There’s also some tips on the page for reducing your computer’s power consumption. Good for the frugal (and at this time of the year in the northeast, that’s pretty much all of us).