DNSChanger is a real piece of malware, it's a variant of the TDSS/Alureon
family of Trojans. It was a real problem until taken down November 8, 2011,
in a joint FBI & Estonian police action and the FBI and BINDS follow up
action that replaced the malicious servers with legitimate DNS servers. The
trojan CANNOT now function as intended BUT many PC users might still be
infected without knowing it. (in System Utilities)