A long but interesting article about Albert Gonzalez, the convicted hacker, in The New York Times Magazine.
After being caught due to the chance observations of a N.Y.P.D. Detective he worked by day for the U.S. Secret Service then went home and enriched himself using information from Secret Service investigations. He used information from government investigations to betray and set-up other hackers, all the while pocketing the money the other hackers paid him for credit card data.
The Secret Service let the fox into the hen-house for sure.
A very interesting read.