Here, Progressive Auto Insurance works its space at the bottom of the page in USA Today's Life Section, with an ad that follows the shape of an umbrella. If not for a thin black border, the ad would blend in completely with the newspaper's "table of content" area. Taking a quick glance, a reader might think the ad is a teaser for a newspaper article featuring Flo, the gal from the Progressive ads. (I wonder, might this ad have been even more eye-catching with reversed-out type and a dark background?)
Nevertheless, the next time you have a space ad assignment, inquire with the publication about shapes other than squares or rectangles. You might find some creative leeway you can use to make your ad stand out from the clutter.