Every single day, more than 500 web sites are attacked by Distributed Denial of Service (DDOS) attacks. Under such an attack, a virus program replicates itself through Email and then, at a pre-set or directed time, every infected computer's Email system sends a signal to the target site, shutting it down with the overload. Such attacks used to be fairly rare, but hackers wrote and distributed programs to create such attacks, and thousands of would-be hackers (many of them teenagers, many in foreign countries) have the software and regard it as "fun" to launch such attacks. The FBI and Secret Service can only investigate a few of the cases, and only rarely can they trace the attack to the hacker who programmed it. The attacks are basically a random background noise on the Internet, and while 500 attacks per day sounds like a lot, there are millions of sites so the actual impact is small. If you ever tried to go to a web site and were blocked by a 'heavy traffic' reply, it is entirely possible that the site has been shut down by a DDOS attack (at least for a few hours). Should, however, information warfare specialists of an enemy (nation or organization) really want to hurt a target country, they could spend weeks of concerted effort setting up a million such attacks, directed at government and industrial sites, all timed to coincide with some foreign policy move or military adventure.--Stephen V Cole