A friend of mine who has an iMac is in the midst of getting it decontaminated with the help of his ISP, it has been hijacked and is generating spam. He has told me that when it is cleaned up he is very likely to come to me for advice on how to keep it clean.
I have opened this topic for two reasons. One is that it does not seem to have been discussed on the forums since the Spring of last year, and a lot can change in that time. Two, I haven't used an Apple computer in a very long time, Windows PCs is where I have some competence.
I have noted Grindler's Mac Rogue tools, and some quick research shows that there are A/V products for Apple computers - for example Avast which I use on both our household computers - but there seems to be very little, if any, anti-malware software available. I am thinking of things like SuperAntiSpyware and Malwarebytes, and I would be grateful for any advice and/or suggestions.
Interestingly, this is the second case of hijacking among my acquaintances in a month or so, and the other was on a PC running XP SP3. But the spam e-mails generated were almost identical, both involving appeals for financial assistance after being mugged in Spain.