Hackers that use their skills for good are classified as "white hat." These white hats often work as certified "Ethical Hackers," hired by companies to test the integrity of their systems. Others, operate without company permission by bending but not breaking laws and in the process have created some really cool stuff. In this section we profile five white hat hackers and the technologies they have developed.

1. Stephen Wozniak: "Woz" is famous for being the "other Steve" of Apple. Wozniak, along with current Apple CEO Steve Jobs, co-founded Apple Computer. He has been awarded with the National Medal of Technology as well as honorary doctorates from Kettering University and Nova Southeastern University. Additionally, Woz was inducted into the National Inventors Hall of Fame in September 2000.

Woz got his start in hacking making blue boxes, devices that bypass telephone-switching mechanisms to make free long-distance calls. After reading an article about phone phreaking in Esquire, Wozniak called up his buddy Jobs. The pair did research on frequencies, then built and sold blue boxes to their classmates in college. Wozniak even used a blue box to call the Pope while pretending to be Henry Kissinger.

2. Tim Berners-Lee: Berners-Lee is famed as the inventor of the World Wide Web, the system that we use to access sites, documents and files on the Internet. He has received numerous recognitions, most notably the Millennium Technology Prize.

While a student at Oxford University, Berners-Lee was caught hacking access with a friend and subsequently banned from University computers. w3.org reports, "Whilst [at Oxford], he built his first computer with a soldering iron, TTL gates, an M6800 processor and an old television." Technological innovation seems to have run in his genes, as Berners-Lee's parents were mathematicians who worked on the Manchester Mark1, one of the earliest electronic computers.

3. Linus Torvalds: Torvalds fathered Linux, the very popular Unix-based operating system. He calls himself "an engineer," and has said that his aspirations are simple, "I just want to have fun making the best damn operating system I can."

Torvalds got his start in computers with a Commodore VIC-20, an 8-bit home computer. He then moved on to a Sinclair QL. Wikipedia reports that he modified the Sinclair "extensively, especially its operating system." Specifically, Torvalds hacks included "an assembler and a text editor…as well as a few games."

4. Richard Stallman: Stallman's fame derives from the GNU Project, which he founded to develop a free operating system. For this, he's known as the father of free software. His "Serious Bio" asserts, "Non-free software keeps users divided and helpless, forbidden to share it and unable to change it. A free operating system is essential for people to be able to use computers in freedom."

Stallman, who prefers to be called rms, got his start hacking at MIT. He worked as a "staff hacker" on the Emacs project and others. He was a critic of restricted computer access in the lab. When a password system was installed, Stallman broke it down, resetting passwords to null strings, then sent users messages informing them of the removal of the password system.

5. Tsutomu Shimomura: Shimomura reached fame in an unfortunate manner: he was hacked by Kevin Mitnick. Following this personal attack, he made it his cause to help the FBI capture him.

Shimomura's work to catch Mitnick is commendable, but he is not without his own dark side. Author Bruce Sterling recalls: "He pulls out this AT&T cellphone, pulls it out of the shrinkwrap, finger-hacks it, and starts monitoring phone calls going up and down Capitol Hill while an FBI agent is standing at his shoulder, listening to him."

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