Great Regulars: Pumped out by networks (botnets) of

malware-enslaved personal computers, unwanted e-mail--random junk, ads, porn, viruses, Trojan horses, get-rich-quick offers from Nigerian nobility--makes up most of all e-mail sent in the world. By far. Estimates range around 80 percent--but a 2007 Microsoft security report in October put it at 97 percent. It ranges from crud to criminal. As for malware, the United States has about 2.2 million computers (more than any other country) infected, according to Microsoft numbers (likely to be low).

from John Timpane: The Philadelphia Inquirer: An army of techies waging war on spam

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