In a long career of conquering huge manufacturing challenges, Elon Musk might have just undertaken his biggest challenge yet. Last week, he introduced Terafab.Terafab marks Musk's latest in a long line of audacious bets, this time homing in on semiconductor production.Fabricating leading-edge semiconductors is one of the most difficult manufacturing challenges in the world -- perhaps the most difficult. So why does Musk think he can pull it off? And how can investors gain exposure to this massive project? T ...