1. Kevin Mitnick: Known as one of the most notorious hackers, Mitnick gained unauthorized access to numerous computer systems, including those of major corporations and government agencies.
2. Gary McKinnon: McKinnon hacked into 97 U.S. military and NASA computers, causing significant disruption and damage. He claimed to be searching for evidence of UFOs and free energy technology.
3. Adrian Lamo: Lamo gained unauthorized access to various high-profile computer networks, including those of Microsoft, Yahoo!, and The New York Times. He was known for reporting his own hacking activities to authorities.
4. Albert Gonzalez: Gonzalez was involved in several major hacking incidents, including the theft of millions of credit card numbers from companies like TJX and Heartland Payment Systems. He was eventually arrested and sentenced to prison.
5. Anonymous: Anonymous is a loosely associated international collective of hackers and activists. They have been involved in various cyber-attacks, such as distributed denial-of-service (DDoS) attacks on government websites and corporations.
6. Lizard Squad: Lizard Squad gained notoriety for launching DDoS attacks on gaming networks, including Xbox Live and PlayStation Network. They also claimed responsibility for hacking into the Twitter and PlayStation Network accounts of prominent individuals.
7. The Equation Group: The Equation Group is a highly sophisticated cyber-espionage group believed to be associated with the U.S. National Security Agency (NSA). They have been involved in various advanced hacking operations, including the development and deployment of malware.
8. Fancy Bear (APT28): Fancy Bear is a Russian state-sponsored hacking group that has been involved in numerous cyber-espionage campaigns. They are known for targeting government organizations, military institutions, and political entities worldwide.
9. Carbanak: Carbanak is a cybercriminal group that specializes in financial hacking. They have targeted banks and financial institutions, stealing hundreds of millions of dollars through sophisticated techniques like spear-phishing and malware attacks.
10. Stuxnet: Stuxnet is a highly complex computer worm believed to be developed jointly by the U.S. and Israeli intelligence agencies. It was designed to target and disrupt Iran's nuclear program by sabotaging industrial control systems.