Danielle Chiesi made a name for herself by building close personal (allegedly intimate) relationships with powerful men, in exchange for company secrets, which she then passed on to Raj Rajaratnam, the leader of what is being called the largest insider trader ring ever.

FORBES: Insider Trading, Not Just for Men Anymore

Investigators are considering a range of possible motives, including unlawful financial gain, theft of trade secrets and a national-security threat designed to damage the exchange.

WSJ: Hackers Penetrate Nasdaq's Computers