I know there are a few other CDers who have Macs - one of the advantages of them is that they are much less prone to viruses, trojans etc.    today a very genuine looking  page popped up on my screen, looking like it was from apple, advising that there was malware/trojans on various parts of my macbook and that I should download the programme to secure my machine and remove virus - it then lauched itself and started to download, each time I clicked out of it it went into download again!  After about 4 downloads I managed to get out of download, trashed everything I could see, and went straight to the Apple help page - there is an official notification of this malware there, details of how to search and destroy the software if it does download (thankfully, after following the steps it had not managed to get going on mine).

This is a very sneaky bit of software, fellow MAc users be aware and avoid downloading, if it does it itself trash straight away and go to mac help.

Thanks for that Gwen, will be on the look out from now on.