Cached copy of  http://support.apple.com/kb/HT2550?locale=en_US&viewlocale=en_US
[missing from Apple site as of 2009-01-27]

Mac OS: Antivirus utilities 
Last Modified: December 02, 2008 
Article: HT2550 
Old Article: 4454 

Summary
Learn about antivirus utilities available for the Mac OS.

Products Affected
Consumer Software, Mac OS

Apple encourages the widespread use of multiple antivirus utilities so 
that virus programmers have more than one application to circumvent, 
thus making the whole virus writing process more difficult. Here are 
some available antivirus utilities:

Intego VirusBarrier X5, available from the Apple Online Store
License: commercial
  
Symantec Norton Anti-Virus 11 for Macintosh, available from the Apple 
Online Store
License: commercial
  
McAfee VirusScan for Mac
License: commercial 
Important: Information about products not manufactured by Apple is 
provided for information purposes only and does not constitute Apple’s 
recommendation or endorsement. Please contact the vendor for additional 
information.

//

Found on Apple on 2009-01-27 ... page about "ProtectMac":
http://www.apple.com/downloads/macosx/networking_security/protectmacantivirus.html