This might have already been said, but whatever happened to ads based on the content of the page you are on? If I'm reading an article about manufactured homes,

This might have already been said, but whatever happened to ads based on the content of the page you are on? If I'm reading an article about manufactured homes, an ad linking to a manufactured home seller could be actually useful. Granted, I haven't turned of my ad blocker in a very long time, so maybe they still exist?