Sendai s new position pays far more money than his modest lifestyle requires. After tiring of watching the money stagnate in his checking account, Sendai opens a brokerage account and begins to dabble in investing. As with hacking, Sendai learns everything he can about investing. Interestingly, he finds many parallels between the two disciplines. Many books and articles suggest filling a portfolio with funds that passively track broad indexes such as the S&P 500. This insures diversity and reduces the risk of bad timing or stock-picking mistakes. Sendai discards this advice immediately. It sounds too much like the conventional wisdom that computer and telephone users should restrict themselves to advertised behavior, and stay ignorant about how the systems work. Sendai prefers stretching system capabilities to extract as much value as possible, based on a comprehensive understanding. In other words, he wants to (legally) hack the financial markets.

Sendai soon discovers another aspect of investing that is familiar to him. Successful active trading is all about obtaining relevant information before it is widely recognized and reflected in the stock price. This is similar to the security market, where the value of an exploit degrades quickly. The Holy Grail is a zero-day exploit, meaning one that is not publicly known or patched. Attackers who possess such an exploit can break into any system running the vulnerable service. The attack is unlikely to be detected, either, because administrators and IDS systems are not watching for what they do not know exists.