I have some bookmarks on my work computer which I will add here tomorrow which gives a even better insight to part viruses or worms which were available for Mac, but almost never seen in the wild.

I personally like the idea of running a Antivirus on my Mac which TARGETS WINDOWS viruses, since it uses the (*mostly inadequate) Signature files for Windows viruses.

This allows me to Clean or remove viruses from people’s external hard-drives and memory sticks (way too often) – and then tell them that we will be re-imaging their machine, and that they should start backing up their data in the mean while.

You see on a Windows PC it is impossible to confirm that the machine is clean after an infection – the only way to be sure is a low level format and a clean install.
This came from the mouth of one of Microsoft’s lead security Specialists – Believe it was Mark Russinovich. [I'll have to provide the link I presume - tomorrow]

Corporately paying for a piece of software such as Symantec isn’t my idea, but contracts are contracts. ClamXAV is great since it’s got a low memory footprint and is free…

Linux users can be good netcitizens by installing ClamAV
http://www.clamav.net/download/packages/packages-linux and try to save those poor souls still dependent on Windows.

Foot note : Vista and Win7 makes life a bit better for Savvy users, but for normal users unfortunately Viruses and worms still get in. (It’s the foundation that is bad, and you know what they say about foundations)