Virus and malware protection for the Mac
Wil Limoges suggests some security apps for the Mac when you, or the users in your environment, need an extra layer of protection against malware.
ZoneAlarm Free Antivirus + Firewall
Need a free security suite? ZoneAlarm Free Antivirus + Firewall combines excellent personal firewall protection with good malware blocking. Note, though, that it may have trouble cleaning up a badly-infested PC.
Malwarebytes Anti-Malware Free
Malwarebytes Anti-Malware Free's defense against zero-day exploits makes it a useful addition to your antimalware toolkit.
Two free Mac antivirus apps compared
The donationware ClamXav and the free Sophos Anti-Virus for Mac combine real-time protection, automatic updates, and on-demand malware scanners to help prevent infections. Originally posted at How To
Microsoft Security Essentials 4.0
Microsoft Security Essentials 4.0 does a decent job protecting a clean PC, but in testing its cleanup of already-infested systems wasn't thorough. You can get better protection for the same price.