How small a footprint?

I read an inspiring story today in the New York Times about a family trying to live with "no impact" in Manhattan ("The Year Without Toilet Paper"). This family of three limited use of all transportation using carbon-based fuel, including mass transit; reduced to nothing their trash output; composted all organic refuse; eschewed elevators; and more.

While I'm not inclined to go quite to the extent they went — I'm not giving up toilet paper — I had to ask myself, "How could I do better?"

What am I doing now and how could I be doing more? I'm nearly pathological about recycling, but could I reduce the amount I am recycling by reducing items I purchase in disposable containers? I use plastic grocery bags multiple times, but should I reduce the number of bags I accept from the store? I drive a hybrid, but could I walk more? (Once weather cooperates, which means getting warmer, I'm all over that.) I keep my thermostat lower in the winter and higher in the summer than my neighbors, but is it low or high enough? I try to turn off lights when I leave the room — but should I continue to put my computer on "sleep" rather than turn it off at the end of the day? (It is purely for the convenience of checking the temperature in the morning before my run). I take the stairs except when my arms are too full — should I carry my lunch bag and books more efficiently?

Every little bit makes a difference. Every trip on the elevator at the office counts. Every time I turn on my space heater so my fingers are warm enough to feel the keyboard costs. It's like eating candy from the dish every time I walk past and wondering how the extra pounds wind up on my fanny. I want to make a difference, and I want to be good to Mother Earth. I want to do right, and I will keep trying as best I can.