Who tops the world for spam? If you guessed the USA, you'd be right. According to security vendor Sophos, America is still the best when it comes to spam.

The firm's quarterly list of countries that send spam, 14.6 per cent of the world's emails originate in the USA. The country has held that position for the year. After all, the US did invent electronic spam.

What makes the US the top spammer these days is the large pool of unsecured - or poorly secured - computers that are infected with malware.

In second place comes the tiny former-Soviet state of Belarus. Although its average is only a third of the USA, per capita makes it the next highest. It is estimated that only one of every e-mail sent is not spam.