botnet
n.— «The major difference between a bot in a botnet, and your common eggdrop or IRC client script bot in a channel, is that the botnet variety have been created with a trojan and, almost always, without the knowledge of the person whose computer they are running from.» —“Just What Is a Botnet?” by Curve DALnet Jan. 2003, 2002. (source: Double-Tongued Dictionary)