Tesla MotorsIn 2000, environmentally conscious Silicon Valley engineer Martin Eberhard was shopping for a sports car with low emissions. The search was fruitless, but it led Eberhard to build the breakthrough Tesla roadster, a $92,000 two-seater that can go from zero to 60 in four seconds, powered entirely by lithium-ion batteries - and it looks sexy. Production starts this fall; the first cars (380 have been preordered) will start hitting the road by the end of this year. A family-friendly four-door sedan that'll cost half the price of the roadster is scheduled for production in 2009. --J.L.Y.