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-- Pay Per Click Engines
---- Report: Botnets Increasingly Used In Click Fraud
brotherhood_of_LAN - 9:44 pm on Jun 16, 2008 (gmt 0)Thread source:: http://www.webmasterworld.com/ppc/3675844.htm
I'd bet some of them are programmed to 'wander' the net and click on other peoples ads/links to appear more natural.
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