Fuel for thought.

The Hot Buttered Rum String Band, a San Francisco area bluegrass group, is committed to using its music as a vehicle to encourage grassroots environmental, social and political change. Even the band's tour bus carries an environmental message.

Hot Buttered Rum String Band's Bio-Bus is a diesel school bus that has been converted to run on recycled vegetable oil. The band bought the bus from students at Vermont's Middlebury College on the Internet auction site Ebay in late August of 2003.

While the Bio-Bus may evoke images of Ken Kesey's Merry Pranksters Psychedelic Bus and the Electric Kool Aid Acid Test, the Hot Buttered Rum String Band has a more sober vision. The band's members hope to educate and to empower people to consider using alternative fuel. And they appear to be in good company, as Neil Young's and Bonnie Raitt's bands have also chosen bio-diesel fuel for their tour vehicles.

"We oppose the environmental degradation resulting from fossil fuel use, yet our musical goals necessitate continuous travel around the country," band member Zac Matthews says. "The Bio-Bus enables us to remain true to our values and to show people a sustainable alternative to conventional transportation."

The band has been touring in support of their latest CD In These Parts, which was released in December 2003.