• by Laurie Sullivan  @lauriesullivan, June 14, 2010

Yahoo has begun offering an ad unit on its log-in page that combines rich media options such as video with Bing-like interactive features found on Microsoft's search engine home page.

  Chevrolet became the first brand Monday to serve up an ad in the space. The campaign runs for three days from June 14-16 to promote the brands Malibu, Traverse and Equinox. Each ad takes over the page for 24 hours.

  Developed in-house, the log-in page ad unit relies on Yahoo's rich media technology to connect consumers with the brand and deliver an emotional experience similar to a painting on a canvas. That ad unit is part of Yahoo's Digital AdVentures program, announced earlier this year.

  The ad unit captures the attention of subscribers, according to Mitch Spolan, Yahoo's vice president of North America field sales. "There only two things to do on this page and that's interact with a beautiful image and log into your Yahoo account," he says. "There's not a search box, link to read news or other content to consume someone's time."

  The ad unit -- 1,400 pixels wide -- produces little competition from rivals that give brands a canvas to tell a story. Industry sources estimate the cost for an ad running on a page this size, driving about 26 million unique users daily in the U.S., would run about $100,000 per day. Sources compare it with a smaller ad on Yahoo's home page, which might run between $250,000 and $600,000 daily.

  About 26 million unique users in the U.S. come through the log-in page that connects Yahoo subscribers with their email account, stock page, and other services. The log-in page is the third-largest property on Yahoo. Spolan says it drives so much traffic that it's almost like talking with one in 10 Americans each day.

  "I'm not convinced the log-in page is a lucrative position for a takeover ad," says Aaron Goldman, principal at Connectual. "Since the person goes to the page to complete an action, I don't think they're open to third-party messages."

  Nevertheless, major brands like Chevrolet that are willing to take a chance have a choice to purchase either a static or interactive version of the ad unit. The static version offers a hot link to another Web site that allows people to learn more about the brand. The interactive version of the ad unit supports video and mouse-over technology that provides more information on products and services. It also can run a trailer of a movie.