Isn't this similar to late '90s browser add-ons that used to pay you to have their ads always displayed?
I'm not very into this advertising mumbo jumbo, but you might be wrong here, since Google have AdWords/AdSense on couple more sites than the search pages. :)
Long story short, there were these companies that either had a browser add-on or a stand alone app that filled 10-30% of your screen with ads, for which you were paid by hour.
Some networks were so successful they even give free PCs :)
- https://en.wikipedia.org/wiki/Pay_to_surf - http://edition.cnn.com/2003/TECH/ptech/12/17/free.pc.reut/ - http://www.angelfire.com/pe/home4u/cl204.html