Biodiesel is available now as a blend (B20) or as a pure fuel (B100).  I have been researching biodiesel since I got my '82 westy diesel, and this fuel looks like good news.  

Reduced emissions, particulates, and a 100% sustainable fuel.  I believe it is classified as a cooking oil, so personal storage of 55 gal drums of the fuel may be possible in your garage.  Check with your fire dept. hazmat regs.  

I am also checking with my local Public Works department because they are running B20 in all of their trucks and heavy equipment.  I am hoping to buy biodiesel from them.  Alternatively a company called World Energy Envirodiesel will ship biodiesel to your door in 55 gal lots.  The cost per gallon is a bit higher due to shipping costs, so forming a buying Co-op may be a good idea.

There is a conversion available that allows one to burn un-refined vegetable oil (from your local restaurant - they may pay YOU to get rid of it)  The kit involves a switch that allows you to start with pure diesel (or refined biodiesel) and switch over to cooking oil when the engine warms up (there is a heat exchanger around the fuel feed line that keeps the oil fluid) and when you are done traveling, switch over to diesel to flush out the injector lines.  

Here are some interesting links:

D.O.E. Biodiesel information site (requires Adobe acrobat reader)
http://www.biodiesel.org/default2.htm

National Biodiesel Board (lots of good links)
http://www.biodiesel.org/default2.htm

World Energy's Envirodiesel (they ship Biodiesel to your doorstep)
http://www.worldenergy.net/Individual_buyers.html

This is a really comprehensive comparison of diesel and gas engine theory
http://www.diesel-central.com/News/cackle.htm

Grease Car site (vegetable oil conversion)
http://www.greasecar.com/Home.html

Veggie Van site
http://www.veggievan.org/

World Energy Envirodiesel 
http://www.worldenergy.net/Individual_buyers.html

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