More than 60 percent of a family's carbon emissions come out of the tailpipe, so reducing trips, buying the most fuel economic vehicle that suits your family and taking public transportation or (gasp!) walking will do the most to curb your CO2. (Here's a handy breakdown of your CO2 carbon contribution.)

Even before reading this article I was thinking about my greenhouse gas emissions as I drove to the Blockbuster to rent a DVD (which of course I combined with a trip to the adjacent supermarket).

But how much carbon is emitted during all of the trips by folks driving alone to Starbucks and video store rentals each year? This has to be in the millions of tons of CO2, all in the name of convenience.

We have even more convenient alternatives that come with some compromise. You can rent movies online, have them mailed to you ala Netflix or through video on demand, which may cost a bit more and the selection may not be the same. Let's hope that someday you'll have the same choices (or better) of selecting your DVDs from the remote control.

You can also buy the coffee beans and make a pot at home, which may not taste as good as Peet's, but at least you won't have to get out of your pajamas before sipping the first cup or drive those extra miles each week.