If you haven't already noticed... pop-ups often lie in wait now, like a time-bomb. "Pop-under" strategy is also getting very popular. You can be many sites away from where it got into your system before it presents itself, there's even a family of them that wait for the next time you activate your browser to show themselves. Just 'cause it popped up while you were on 'rosity doesn't mean it has anything to with here. Get a good pop-up killer and a firewall.