Finding the notorious Clampi banking Trojan on a computer inside your network is a little like spotting a single termite crawling into a crack in the wall: Chances are, the unwelcome little intruder is part of a much larger infestation. At least, that’s the story told by two businesses which recently discovered Clampi infections, compromises that handed organized cyber gangs the access they needed to steal tens of thousands of dollars. In early August, attackers used Clampi to swipe the online banking credentials assigned to the Sand Springs Oklahoma School District. The thieves then submitted a series of bogus payroll payments, totaling more than $150,000, to accomplices they had hired throughout the United States. Sand Springs Superintendent Lloyd Snow said the district has since been able to get about half of those transfers reversed, while the district’s bank graciously covered the rest of the loss. Initially, Snow said, suspicion fell