Several of you have had your email address lists hacked (I've had many spam emails over the last week purporting to come from various member's email addresses) - most seem to be Yahoo accounts. The link in the emails being sent is just a spam advert - nothing malicious. The originators have installed the "advert" page by hacking into a number of perfectly "normal" web servers around the world and seem to have hacked personal computers to collect address lists.
I know it's been said many times but never, ever, ever, ever click on a link in an email even if you think you know the sender or what it's about. Don't download or install anything "free" or that you're told you need to stop your computer dying unless you are ABSOLUTELY sure of it's origin (check for a product web site for starters)!