Top 3 hackers

1. Jonathan James
He was sentenced at 16 years old. In an interview, he professes, "I was just looking around, playing around. What was fun for me was a challenge to see what I could pull off."

James's major intrusions targeted high-profile organizations. He installed a backdoor into a Defense Threat Reduction Agency server. The DTRA is an agency of the Department of Defense charged with reducing the threat to the U.S. and its allies from nuclear, biological, chemical, conventional and special weapons. The backdoor he created enabled him to view sensitive emails and capture employee usernames and passwords.

James also cracked into NASA computers, stealing software worth approximately $1.7 million. According to the Department of Justice, "The software supported the International Space Station's physical environment, including control of the temperature and humidity within the living space." NASA was forced to shut down its computer systems, ultimately racking up a $41,000 cost.

However, he served six months in prison for violation of parole.

2.Adrian Lamo
lamo's claim to fame is his break-ins at major organizations like The New York Times and Microsoft. Dubbed the "homeless hacker," he used Internet connections at Kinko's, coffee shops and libraries to do his intrusions.

When he broke into The New York Times' intranet, things got serious. He added himself to a list of experts and viewed personal information on contributors, including Social Security numbers. Lamo also hacked into The Times' LexisNexis account to research high-profile subject matter.

For his intrusion at The New York Times, Lamo was ordered to pay approximately $65,000 in restitution. He was also sentenced to six months of home confinement and two years of probation, which expired January 16, 2007. Lamo is currently working as an award-winning journalist and public speaker.

3.Robert Tappan Morris:
Morris, son of former National Security Agency scientist Robert Morris, is known as the creator of the Morris Worm, the first computer worm to be unleashed on the Internet. As a result of this crime, he was the first person prosecuted under the 1986 Computer Fraud and Abuse Act.

Morris wrote the code for the worm while he was a student at Cornell. He asserts that he intended to use it to see how large the Internet was. The worm, however, replicated itself excessively, slowing computers down so that they were no longer usable. It is not possible to know exactly how many computers were affected, but experts estimate an impact of 6,000 machines. He was sentenced to three years' probation, 400 hours of community service and a fined $10,500.