ClamXav

ClamXav is a virus scanner for Mac OS X. It uses the very popular ClamvAV open source antivirus engine as a back end and has the ability to detect both Windows and Mac threats.

ClamXav can be setup up as passive or active: scan only the files you tell it to or your entire hard drive, whichever you prefer; you can also choose to activate Sentry to monitor your hard drive and scan new files as they arrive.

Features

Clean, simple-to-use interface Clearly lists infected files Free virus definitions (usually updated daily) Save your favourite scan locations for easy access Customise the toolbar - or hide it entirely Send selected files to quarantine or trash with one click Specify files to exclude using plain text* or by using drag & drop from the Finder Specify schedules to update virus definitions and perform scans Use ClamXav Sentry to monitor your hard drive and scan new files as they arrive Use the bundled ClamAV engine or bring your own installation Compatible with Mac OS X 10.5, 10.6, 10.7, and OS X 10.8 Mountain Lion

What are the differences between the version of ClamXav available to download here and the version on the Mac App Store?

The App Store version doesn't contain ClamXav Sentry, so it is not able to watch your computer for new files and scan them as they arrive. There is no engine installation phase as the App Store requirements stipulate that everything must be self-contained within the app. Virus definition updates are downloaded on a per-user basis. Updates to the ClamXav app itself are taken care of via the Mac App Store. Mac OS X 10.6 or greater is required.