Mathematician
Reason, and reason again
A Dim Bulb - Your local hardware store probably sells a regular incandescent bulb for $2 or $3. Compare that to a compact flourescent bulb that sells for about $15.00. No contest you say? Think again. Experts say you may buy 10 or more of the cheaper bulbs over ten years, compared to only one of the more expensive type. Now which looks better?
Idle Time - Ever wonder if you should leave the car running while you wait for the kids to be dismissed from school? Leave it on if you'll be there less than a minute, otherwise it's more efficient to turn it off and restart it when you're ready to go.
Office Paper - Does your office recycle? Chances are it generates a vast amount of clean paper waste. Ask your building management about recycling programs. If none are in place, then put boxes (marked "Recycled Paper Only") under every desk and next to copiers. Arrange to have a recycler pick them up or take them to a recycling facility periodically.
Arbor Day - Here's the best idea of all: Plant a tree, or two, or even three. They're beautiful, they provide shade, consume CO2 (that's good), and they produce oxygen. Breathe it in. Then go plant a tree.
More tips found at http://interiordec.about.com/library/weekly/aa042201a.htm
Remember, Mother Earth sustains us all! For 200,000 years she has given us everything our species needs. You can repay her in two minutes by following these simple tips.