Even though he's a country star, Willie Nelson is the king of the rock-star bus. The singer who proclaimed, "like a band of gypsies, we go down the highway," is on the road a reported 135,000 miles each year. His bus is more than a means of conveyance, like many legendary tour buses, it's a rolling party. In 2006, Willie was busted in Louisiana with 1.5 lb. of marijuana and also mushrooms, and later on Interstate 10 outside El Paso, Texas, with 6 oz. of pot. Keeping it natural, in recent years Willie has used a bus fueled with "Biowillie," a biodiesel fuel made of soybeans and vegetable oils. (No word on whether the activities on board have changed.)