Our two favorite countries, U.S. and India, are the top spammers in the world, according to a new report from computer security services provider Sophos.

U.S. is the leader of the spammers, accounting for 18.6% of spam in the July-September 2010 quarter, up from 15.2% in the previous quarter.

India’s share of spam was 7.6% in the third quarter.

Much of the spam is said to come from malware-infected PCs that are controlled by cyber-criminals who trick users into clicking malicious links in spam e-mail or social networking messages.

Here’s the ‘Dirty Dozen’ list of Top Spammers: