Separate audiences from the page and on top of that, fragment the audiences into singular conversations (impressions).
In order to buy single targeted impressions, you must have data on the impression. Data is key. Dare I say, data is the new king (content)? If you have data and aren't afraid to roll up your sleeves and analyze it, you can do some really interesting things today. Just having data however does not mean a thing ... quantitative analysis and modeling abilities will allow everyone from agencies to technology companies to create unique audience segments and add color to single impressions.
Whether you're a venture capitalist looking for your next investment, a media planner/strategist looking to figure out where to spend your ad dollars or a brand manager looking to grow your P&L, there is no shortage of companies emerging (or that have emerged recently) that could provide this data.