By Matthew Goldstein

PHILADELPHIA, Feb 19 (Reuters) – An office building that sits atop an upscale shopping mall in downtown Philadelphia is not the sort of place that would ordinarily strike fear into the hearts of bad guys on Wall Street.

But that is home turf for the little-known regulator who has built a better mousetrap: an increasingly sophisticated computer database which is already helping the U.S. Securities and Exchange Commission catch insider traders.

Last month, Daniel Hawke, an energetic, guitar-playing 46-year-old lawyer, was named head of a new task force charged with cracking down on a variety of market abuses.

Even before the promotion, Hawke, who remains director of the SEC’s Philadelphia office, cast a surprisingly long shadow over the financial industry from his perch a two-hour or so drive from the canyons of Wall Street.

A few weeks after hedge fund billionaire Raj Rajaratnam was arrested in New York last October in the most significant insider trading investigation in two decades, Hawke and his team of lawyers were busy working to reel in the next big catch.