After reading Dino's article about the DNSChanger Botnet Malware virus, I found a utility that checks your Mac to make sure you are not infected.

It is a free download here:
http://macscan.securemac.com/files/DNSChangerRemovalTool.dmg

Dino's article here:
http://www.cortesisland.com/tideline/show4543a/DNSChanger_Botnet_Malware