During the Second World War, almost every motorised vehicle in continental Europe was converted to use firewood.
Wood gas cars (also known as producer gas cars) are a not-so-elegant but surprisingly efficient and ecological alternative to their petrol (gasoline) cousins, whilst their range is comparable to that of electric cars.
Rising fuel prices and global warming have caused renewed interest in this almost-forgotten technology: worldwide, dozens of handymen drive around in their home-made woodmobiles.
----------------------------------------------------------------------------------------------------------------------------------
http://www.lowtechmagazine.com/2010/01/wood-gas-cars.html