Biodiesel and rising fuel prices

Increasingly the media is talking about cleaner fuels and petrol companies are selling cleaner fuels on the forecourt. Despite this I don't meet many people that know an awful lot about biofuels: particularly biodiesel. Which is strange considering that amount that is spent at the petrol pumps. Perhaps petrol companies are making money because of high oil prices. I wonder how much petroleum-diesel is in the fuel I buy.

Below is a good video about the benefits of biodiesel from an American standpoint. One interesting part one reason that you cannot just substitute a biofuel for your ordinary diesel: the fuel is so much cleaner it cleans your engine out dumping a lot of gunk in your fuel filter.