Varied Shapes and Sizes
Banner ads and sidebar ads have standard sizes, but in the last year or two people have tried all different sizes and placements. Here are three examples:
On this page you can see a narrow strip for Netscape at the top, a standard banner ad, a square AOL ad mid-page, and four smaller ads along the bottom.
On this page there is a round WSJ button up top along with ads for Casio, Ubid and Radio Shack along the side. At the bottom there are tiny ads for four money sites along with small ads for CareerBuilder.com and WSJ.com (even the advertising is sponsored!).
Sites don't get paid much for these smaller ads, because generally the click-through rates are low. But by putting 10 ads on the page, it can add up to $2 per 1,000 page impressions.
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