In this approach, the advertiser would display his/her ad along with all the other ads currently on display.
Larger ads have the disadvantage that they will overlap with other ads and may end up being underneath many of them.
Advertisers may resize and/or move their ads at any time to reduce overlap.
Whenever two ads overlap, they will then have to fight it out to see which one will go on top. This fight is on-going and may involve one ad appearing on top, later underneath, then on top again, and so on.
To determine which of two overlapping ads goes on top, we would compare their current scores, where the score of an ad could be the number of visits minus the number of "hide" requests from consumers say.
One can view this approach as a geometric version of social news.
For a non-geometric version of this idea, we could have something like reddit but where the submitter determines and can change the rank of his/her link on the front page.
The issue is that a link ranked highly will have to share that rank with many links. We can have the probability that a user will see a link at rank k depend on the score of that link with respect to the scores of other links with rank k.