I just got clobbered by this lil nasty. It took me most of the day to get rid of it. It opens up a pop-up windo from your system tray notifying you that you have a virus and that by clicking the link, you will be taken to a site where you can download an anti-virus software. Clever little extorsionists they are. Anyway, if you get hit by this thing, there are some really good instructions for getting rid of it at
http://www.2-spyware.com/remove-spywarestrike.html
Sorry if this is old news, but I felt it was worth passing on.