in order to discover the cost of our presence

In order to discover the cost of our presence on Earth, we can buy this little device that checks our energy useage. Mostly it will tell us exactly how much money having a bigger blender or a less efficent refrigerator will cost us.

What's nice about it is you can do a little cost-benefit analysis on any product you own and want to replace, to see how quickly you can make back the money you spent on a new, more energy efficent model!

Here's a guy doing just that over at GroovyGreen.com.