Michael Calce, who went by the online name Mafiaboy when he launched a massive cyberattack at highly publicized denial-of-service attacks in February 2000 against large commercial websites, including Yahoo!, Fifa.com, Amazon.com, Dell, Inc., E*TRADE, eBay, and CNN. He also launched a series of failed simultaneous attacks against 9 of the 13 root name servers. The impressive part is that the attacks were launched almost simultaneously and there was still enough bandwidth to go around to take down multiple high profile sites.
DDoS was a lot easier back in those days, I remember one of the attacks launched at an IRC user that lived in Romania that always made me laugh, instead of just DoS’n the user they DDoS’d the uplink that provided bandwidth to the entire country – YES – they took a country offline with a few servers and good old ./milk.c and ./stream.c
This was back in my hay-day on IRC when there was only a handful of gifted hackers out there, 0day exploits would remain 0day for months and even years. Virtually every single .edu, .gov, .mil, .kr, .jp that ran IRIX/SOLARIS/Linux*/*BSD or any other flavors of *nix were completely owned and were pulled into a DDoSnet using MSTREAM, Trinoo, TFN or Stacheldraht.
After serving jail time he wrote a few books, here is a great read for a few dollars on his adventures:
Mafiaboy: A Portrait of the Hacker as a Young Man