The FBI and federal prosecutors built a case against Ancheta that included reams of IRC and instant message exchanges between him and customers interested in renting access to his botnet to send spam, launch DDoS attacks, or distribute "pay per click" adware and spyware, as well as records of Ancheta's efforts to keep his botnet operating by moving his IRC servers between various Internet hosting companies to avoid being shut down.

Speaking on Monday, Judge Klausner said his crimes were "extensive, serious, and sophisticated," and accused Ancheta of "intellectual arrogance."

"Your worst enemy is your own intellectual arrogance that somehow the world cannot touch you on this," he said, according to a statement released by the U.S. Attorney's Office.

Ancheta's sentence follows news of another successful prosecution of a botnet operator. On May 4, Chris Maxwell, 20, of Vacaville, Calif., pleaded guilty (http://weblog.infoworld.com/techwatch/archives/006225.html) in U.S. District Court in Seattle to computer fraud charges for operating a botnet that caused disruption on critical care systems used by Seattle's Northwest Hospital in January 2005.