But do not lose faith. The exhaust from Nelson's diesel-powered Mercedes smells like peanuts, or French fries, or whatever alternative fuel happens to be in his tank.

While Bono tries to change the world by hobnobbing with politicians and Bob Geldof hosts his megabenefit concerts, Willie Nelson has birthed his own brand of alternative fuel. It is called BioWillie. And in BioWillie, Nelson, 72, has blended two of his biggest concerns -- family farmers and the Iraq war.

BioWillie is a type of biodiesel, a fuel that can be made from a number of crops and run in a normal diesel engine. If it sounds like a joke, a number of businesses, as well as city and state and county governments, have been switching to biodiesel blends over the last year in their transportation fleets. The rationale is that it is a domestic fuel that can profit farmers and that it will help the environment, though environmentalists are not universally enthusiastic about it."We needed to have something that would keep us from being so dependent on foreign oil," Nelson said in an interview this month.

He added, "It seems like that's good for the whole world if we can start growing our own fuel instead of starting wars over it."