After two years of reductions, the United States was unable to further lower the amount of unsolicited e-mail, or spam, generated by computers within its borders during the first three months of 2006. Based on the latest figures released by anti-virus software maker Sophos, the United States remains perched atop the list of the so-called “dirty dozen,” the world’s top 12 spam-relaying countries, a place it has held since Sophos began collecting its data in 2003. Full Story