Ingenio A pay per call ad might look like this.

Rather than bemoaning the fact that Craigslist has stolen the classified ad market or sparring with Google News in the name of "brand preservation," I think it's more constructive for news organizations to look for new revenue sources. I just found out about an intriguing option today at the Search Engine Strategies Local Search conference in Denver: pay-per-call advertising.

Pay per call isn't brand new, but it is a relative newcomer to the advertising marketplace. Here's how it works: A company like Ingenio provides an advertiser with a unique toll-free phone number. That number appears in ads, and forwards to the advertiser's actual phone. This allows calls from the ad to be trackable. The pay-per-call provider then charges advertisers based on leads generated, not the abstract and somewhat surreal concept of "clickthrough" -- which many advertisers (especially small businesses) find difficult to translate into business value.

What's especially cool about this is that it works not only for online advertising, but also for mobile content and even for print or broadcast. At the session I just attended, Ingenio marketing chief Mark Barach explained that print publications can partner with pay-per-call providers to sell excess ad inventory. "Sometimes we'll buy a bunch of excess inventory in a newspaper or magazine and distribute that among our advertisers, but more commonly we'll partner with the publication to add our functionality to their ads and split the revenue."

Seems to me this could be a good way to integrate/upsell advertising across print, broadcast, and online operations. And, of course, it's trackable. In an age where online media is overtaking audience share, advertisers will increasingly demand trackable performance for ads in all media.