The US sends out more spam than the rest of the world put together according to inbox defenders at Sophos. Researchers at the anti-virus firm checked the origins of two days worth of spam, and compiled a list of the worst offenders.

Although the vast majority of spam comes from computers in the US, the picture is not as simple as it appears. Sophos believes that a large percentage of spam actually originates in Russia, with spammers using hijacked PCs in the US to distribute their delightful messages. Yes, yes, but who are the Russians acting for: other Russians, or sleazeball Americans?

Without accounting for any possible hijackings, the figures show the USA accounts for 56 per cent of all spam, with Canada coming a poor second with a 6.8 per cent share. China and Hong Kong sit in third place, followed by South Korea. The full list is here.

The findings, based on analysis of hundreds of thousands of emails examined by researchers using honeypots and other measuring systems, serve to highlight the difficulty of legislating against spam on a national level. As senior tech consultant Graham Cluley points out: "legislation in the UK won't protect users from spam coming from North America or China. ®

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