I sell biodiesel processors that allow you to make high quality biodiesel fuel from waste fryer oil from restaurants for about $1 per gallon. These are industrial grade stainless steel processors, and are easy to use, safe, and make great fuel quickly (48 hours start to finish). The machines have an attached pump so you can pump the finished fuel right out of the machine into your truck or into storage. Biodiesel fuel can be used straight or mixed in any percentage with diesel. It will quiet down the engine and also cleans and lubricates it. I also teach biodiesel classes. Let me know if you have any questions! It pays to buy from someone who really knows biodiesel. Info:  www.biolyle.com