[tim333]

>Both Brin and Page had been against using advertising pop-ups in a search engine, or an "advertising funded search engines" model, and they wrote a research paper in 1998 on the topic while still students. They changed their minds early on and allowed simple text ads.

Sounds like a road map.

(Wikipedia)

[kozak]

But here we should remember what internet ads were like before the appearance of textual Google ads. They were image banners of standardized sizes, much more intrusive and way more pointless.

[jmvoodoo]

I think that depends on your definition of intrusive.