Hacking can, and often does, improve products. It exposes vulnerabilities, supplies innovations, and demonstrates both what is possible and what consumers want. Still, hacking has a dark side, one that has eclipsed its playful, sporty, creative side, especially in the popular imagination, and with good reason. Hacking has become the preferred tool for a certain kind of thief, one who lifts money from electronic bank accounts and sells personal information, particularly as it relates to credit cards and passwords, in a thriving international Internet underground. Hacking has also become a method used for extortion, public humiliation, business disruption, intellectual property theft, espionage, and, possibly, war.