There are a number of sites I'd like to blacklist which have "sponsored links" from my newspaper's website, from cracked, etc. Some are terribly written, some (like answers.com) have adopted an unbelievably annoying, advertising-heavy slide-show design. Click on something like "10 Actors who didn't deserve their Academy Award" and you'll find you have to click 30 times, because each topic gets three slides.. the first a picture and the next two with text (usually just a sentence or two) overlaid over that picture. The slide is, naturally, surrounded by ads, and clicking "next slide" reloads the page with the ads (fortunately quickly from what I've seen).
I have seen this design practice explode in popularity over the last few months. Of course, all the users hate it, and the comments sections have plenty of people complaining about the shitty format. But it does let the website owners claim they delivered lots of ads to the reader!
Also, if "you pay when you click" takes off, look for malware that hijacks browsers and simulates clicks to become prevalent.