alphadogg writes "An upstart Trojan horse program has decided to take on its much-larger rival by stealing data and then removing the malicious program from infected computers. Security researchers say that the relatively unknown Spy Eye toolkit added this functionality just a few days ago in a bid to displace its larger rival, known as Zeus. The feature, called "Kill Zeus," apparently removes the Zeus software from the victim's PC, giving Spy Eye exclusive access to usernames and passwords. Zeus and Spy Eye are both Trojan-making toolkits, designed to give criminals an easy way to set up their own "botnet" networks of password-stealing programs. These programs emerged as a major problem in 2009, with the FBI estimating last October that they have caused $100 million in losses."