Biodiesel is beginning to make its way into the aviation jetfuel market, several flights have already been made using various biofuel combinations. This Delfin L-29 was the first jet aircraft to fly on 100 percent biodiesel and the first to fly trans-continental on biofuel.
At the time of this writing, the current bid is over $30,000 but the reserve is not met. They'll take a MiG 21 in trade though, if you have one in the hanger.
Link: BioJet - auction has ended
