Micro-targeted

One difference that springs to mind is the sheer individualization of it. There are some auctions where you can even bid for an individual human impression. For example, there’s a startup that will let you target a particular person with an ad campaign…

Maybe you want your partner to stop smoking. This startup will generate a special link for you that looks like it’s an e-commerce site. You send it to your partner and when they click it, they get a cookie secretly loaded into their browser. This cookie enables the company to track your partner across the web. You write up an anti-smoking ad, and the company will ensure that your partner sees that ad everywhere. Now your partner’s entire internet experience is permeated with pressures to stop smoking. You can design a similar campaign for a coworker you don't like. You can show them ads for job-hunting websites, to encourage them to get another job.

From The Art of Eyeball Harvesting, by Shengwu Li, Assistant Professor of Economics, Harvard University. Logic Magazine, Issue #6, Play