1. Shawn Fanning – What was once an IRC handle became synonymous with the free exchange of music files. Along with Jordan Ritter and Shaun Parker changed the music industry forever and set the course for the next decade of online media. Managed to turn a cool rock metal band into a bunch of whining babies and had his high moment when he appeared on the MTV music awards wearing a Metallic t-shirt. ADM were also the best and most consistent group ever (wikipedia).
2. Robert Morris – Discovered the buffer overflow and exploited both sendmail and fingerd with the first ever internet worm – now known as the Morris Worm. Went on to become a co-founder of ViaWeb with Paul Graham. Downside is that his story was responsible for Dade Murphy and the Gibson OS, but it also bought us Angelina Jolie. (wikipedia)
3. VallaH - jolt.c and the ping-of-death kept kids around the world amused for years and big corporations on their knees. The first smart denial-of-service attack.
4. Gordon Lyon / Fyodor – Created Nmap, the
first tool in every hackers arsenal that has since gone on to make cameo appearances in both The Matrix and the Bourne Ultimatum. Nmap pioneered OS and service fingerprinting. Also behind insecure.org. (wikipedia)
5. Kevin Mitnick – Most famous real-life hacker who could have used a few tips on how cellular triangulation works. Imprisoned by the government without charge for years and restricted with a gag order thereafter. FREE KEVIN became a hacker freedom call for years. (wikipedia)
6. The Mentor – Wrote the Hacker Manifesto which was published in Phrack magazine. Inspired kids worldwide to hack to learn (myself included). Phrack magazine deserves a mention as it was the best and most consistant e-zine in the past two decades. Ran for 65 issues until 2005.
7. Karl Koch / August Diehl – German hacker in the 80s who drove himself insane with cocaine abuse, obsession over the number 23 and paranoia over the Illuminatus. (wikipedia)
8. Electron / Richard Jones – Aussie kid who wrecked havoc all over the world with nothing more than a modem. Arrested by the Australian Federal Police in 1990. Went on to become a security researcher and consultant.
9. Kevin Poulson / Dark Dante – Phreaked his way to a new Porsche with a radio contest on an LA station. Arrested and jailed and went on to become a journalist and editor at Wired. (wikipedia)
10. Adrian Lamo – showed the world (literally) that you can take down large websites with just URLs (such as Worldcom). Now also a journalist. (wikipedia)