DNSChanger
DNSChanger was a DNS hijacking Trojan active from 2007 to 2012. The work of an Estonian company known as Rove Digital, the malware infected computers by modifying a computer's DNS entries to point toward its own rogue name servers, which then injected its own advertising into Web pages. At its peak, DNSChanger was estimated to have infected over 4 million computers, bringing in at least US$14 million in profits to its operator from fraudulent advertising revenue.