If Safari is your main browser and you’re runnning it as-shipped, your Macintosh is vulnerable as  a Brooklyn-based iPod lover . Bad jokes aside ^* , this is a serious vulnerability that has been targeted by at least  one virus/trojan/worm found  “in the wild”. To fix this problem caused by brain-dead Safari engineering, switch to Safari (you’re likely in it now), go to Safari’s “Preferences”, click on the “General” tab and uncheck ‘Open “safe” files after downloading.’

The above image is a link to a (2.4 MB) video tutorial on  how to prevent Safari from opening so-called safe files .

For those of you prone to getting techy about such issues, John Gruber of  Daring Fireball  has an excellent discussion on  the nature of this vulnerability , as well as some excellent suggestions for Apple’s Safari and Finder programming teams.

 ^*  The loss of Christopher Rose’s life is an unmitigated tragedy, and the metaphorical reference to his murder as an abstract concept is not meant to suggest that his death is merely a laughing matter.