We expect our movie stars to drive sleek, high-end automobiles. So why have Cameron Diaz's Porsche and Mercedes been gathering dust in her garage for the past four months? Because these days the stylish actress tools around Tinseltown in a $20,000 Toyota Prius--a hybrid car that swings both ways, alternately guzzling climate-heating gasoline and sipping environmentally friendly electricity. What the car lacks in class it makes up in fuel savings and reduced emissions. "I love my Prius," says Diaz, 29, who reports that the batteries on her luxury cars have both died from neglect. "The Prius is all I drive."
Bill...