I just read an interesting article in the New York Times about a couple who are involved in a year-long experiment.  For an entire year the couple, along with their two-year-old daughter, will endeavor to live a no impact lifestyle.  The guidelines for this eco-friendly lifestyle include:

• No carbon fueled transportation
• Eating organically grown products that come from within a 250 mile radius of their home
• No producing trash or waste

The last item is what leads to the no toilet paper policy.  (The answer to your unasked question is lots of water and air-drying.) 

To read more about this experiment in REALLY walking the talk visit the blog at www.noimpactman.com.