Experts reckon there are 4,000 radical Islamist websites run by talented people, changing servers every day.
While he calls for a return to the Islam founded in the seventh-century, his communication methods are up-to-the-minute. Abu Musab al-Zarqawi, the head of al-Qaeda in Iraq, turns to the Internet to spread his message of jihad, or holy war.
In audio messages transmitted online, a voice claiming to be Zarqawi takes responsibility for attacks in Iraq, makes threats, comments on the news, and speaks to the American people.
In Monday's message, which CIA analysts believe was authentic, Zarqawi addressed Al-Qaeda's global leader, Osama bin Laden. Zarqawi acknowledged reports that he had been lightly wounded but said he was still fighting with the insurgents to drive the US-led coalition out of Iraq.
The rebel leader, who tops the US most-wanted list in Iraq with a 25-million-dollar reward on his head, is hounded by the American forces. Still, Zarqawi eludes capture and maintains a capacity for organization and communication, according to experts.
"The jihadists in general and Zarqawi in particular use technology very efficiently," said Alain Chouet, a former French intelligence agent.
"They use the Internet on a daily basis; it's integral" to their operation, he said.
Rita Katz, who heads the SITE Institute in Washington that specializes in surveillance and translates Islamist websites, said that "on a daily basis we have four to 10 messages from Al-Qaeda in Iraq. It is not a one-man job. There is no doubt in my mind that he has a team of talented people doing that."
It's easy to send an email message to Zarqawi and get a response. "We have translated many examples of that. His interaction on the Internet is amazing," Katz said.
In the radical Islamist world, Internet usage is encouraged and everywhere.
Jerrold Post, a professor of psychology at George Washington University in Washington and long-time adviser to the Central Intelligence Agency, said he found on an Al-Qaeda website a message urging Muslim professionals to use the Internet to serve the jihad.
"If you fail to do this, you may be held into account before Allah on the day of the judgment," Post cited the website as saying.
"There are something like 4,000 radical Islamist websites out there, changing servers every day. There is no way to stop that from happening and we in the West haven't been countering the effect of their extremist messages," Post said.
Some experts, nevertheless, warn against the risks of falsification and manipulation by Internet enthusiasts.
According to Alain Bauer, a French criminologist and co-author of "The Al-Qaeda Enigma", says that most of the websites are fake.
"Since the beginning of the Iraq war, there has been a profusion of websites making more or less strange demands," he said.
Bauer also noted that Al-Qaeda has become "a sort of franchise name" that different groups use because "it is easier for Westerners to understand."
"It is the efficient use of propaganda."