Sometimes markets err big time. Markets erred when they gave America Online the currency to buy Time Warner. They erred when they bet against George Soros and for the British pound. And they are erring right now by continuing to float along as if the most significant credit bubble history has ever seen does not exist. Opportunities are rare, and large opportunities on which one can put nearly unlimited capital to work at tremendous potential returns are even more rare. Selectively shorting the most problematic mortgage-backed securities in history today amounts to just such an opportunity.