Symantec came out with another very interesting piece of research last week. They published their "Dirtiest Web Sites of Summer 2009". These sites are the worst of the worst security offenders. Common threats include phishing attempts, malicious downloads, browser exploits and links to other unsafe sites.

On average, sites in this list contain an astounding 18,000 threats per site. Forty of the sites on this list have over 20,000 threats. And one particular offender has 23,414 serious security threats. And, finally, the Symantec list contains some information that will refute the notion that extremely dangerous sites are taken down quickly. It turns out that 3/4 of the sites on the list have been hosting threats for more than six months...