Like someone else said, the sites with popups are usually low quality (cept for paysites). See, the way it works is, you go to a link list and click a link off of there. Step through, carefully, to find the pictures, and back out to the link list. If you leave the site you originally clicked on, you'll get pop ups. That's the way the sites are made. You are drawn in off the description on the link list, you see links on the site to something else you like, click that, and you're off in pop-up land.
Surprisingly, pop up ads are very effective for the porn webmaster, increasing sign ups by like 25-30%. Pretty cool. They can also be used for opening up a toplist window that will have a juicy ad saying click here for more porn. You'll click, and the website gets credit, and gets another surfer back to their site in return for your click to that toplist.
I could write a dissertation on how porn websites work. But I'd have to provide lots of links, and I'd get banned in about 3 seconds.
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