ClamXV

ClamXV screenshots

It uses the very popular ClamAV open source antivirus engine.

Alternative downloads

MacScan
3.2
Protect your Mac from malware and privacy threats.
Dr.Web for Mac OS
6.0.3.201204200
It is a reliable and easy-to-use anti-virus application for your Mac.
ClamX anti virus
FREE
It can be setup up as passive or active.