have a 00 transit and fill with 65-70% diesel and 30% vegetable oil, have been doing it for a while now and it works a treat, a guy i know has been doing it for years and swears by it, thats what got me on to it. I just don't know what customs would say if they dipped the tank!
A guy I know uses recyled chip shop oil and takes great amusement from watching the occupants of the car behind him in traffic trying to figure out where is the smell of chips coming from :->>