Where is the most expensive advertising on the Internet?

AdAge compiled a ranking of the most expensive advertising platforms. The analysis used the cost per thousand banner impressions. Yahoo! emerged as the most expensive site for advertisers. A placement on the portal's homepage can cost advertisers up to $400,000 per day.

Prices may vary on other sites, but due to the lack of a unified approach to advertising costs, the publication's specialists were unable to create a single advertising cost rating.

For example, on the AOL homepage, advertisers can purchase branded impressions for approximately $500,000-$700,000 per day. YouTube's homepage costs advertisers $400,000, which includes video placement.

Other top-selling sites include WebMD.com, Marthastewart.com, Forbes.com, Bloomberg.com, Turnet Networks assets (including CNN.com), ESPN's YouTube channel, Economist.com, and the National Journal Energy blog.