A Virgin flight

On Monday, Virgin Atlantic announced that it will undertake the first ever biofuel-powered flight of a Boeing 747. This will take place in February between Amsterdam and London and is mainly so engineers and other assorted boffins can see how much CO2 is saved and - one imagines - whether the poor plane will ever fly again.

But what is more interesting than this is the fact that the good people of Virgin claim they have created a new generation of biofuel that is from a sustainable source and won't mess with our food supply. What people tend to forget when we trumpet biofuel is that it tends to be at the expense of vast swathes of land, often covered by pesky rainforest and the like.

Virgin is staying tight-lipped about this fantastic new sustainable source and I have to admit that - much like the rainforest I just mentioned - I'm stumped. What on Earth is it? What do we have so much of that the airline industry couldn’t exhaust it? Money set aside to bail out Northern Rock? Undeclared political donations? Ex-Newcastle United managers?

Answers on a postcard to the usual address please