http://www.greencarcongress.com/additives/index.html Strides are being made in biodiesel particulate emmisions. But with the recent trend toward biodiesel, what percentage of the total vehicles on the US roads today could be fueled by biodiesel, as the sources stands today? What are the sources of biodiesel?, and would our food supplies be cut short in an effort to supply larger biodiesel deliveries? Also, do any bitogers work at the SWRI, as stated in the article? I think at one time it was called "monkey island". No offense intended.