You think there are no viruses for Macs? Well, think again. Although they are few, compared to the gazzillion-odd forms of malware that exploit vulnerabilities in Microsoft Windows systems and applications, they do exist.
My favorite anti-virus application, Sophos, has now release a free home version of it's AV program for Macs!
You can download it at:
http://www.sophos.com/products/free-tools/free-mac-anti-virus/
Also, if you want to read up on malware for Macs, check out the following website, put together by Sophos:
http://nakedsecurity.sophos.com/2010/11/02/anti-virus-mac-free/
