There's a strong fascination cum infatuation with semi-secret rules that explain why we do what we do. Even In Treatment uses Gladwell (the form's biggest popularizer) to forward a common misconception about therapy while creating dramatic tension.

In a recent counter-intuitive example, a study indicates that people ordering from a menu that includes healthy and less-healthy options will feel more free to choose the less-healthy option. The theory isn't totally clear (perhaps a vicarious "I've been good" hit comes from the presence of those other items) and its extensibility to other choice behaviors isn't at all clear.

And in the "no duh" category, another study that looked at radiologists found that "when a digital photograph was attached to a patient's file, radiologists provided longer, more meticulous reports. And they said they felt more connected to the patients, whom they seldom meet face to face." Although I wonder if the folks at the passport office, with their surplus of mortifying headshots, would support this study, it really just makes sense and could be applied to all sorts of intermediated interactions, both asynchronous (i.e., mortgage applications) and synchronous (ie., tech support chat). For further study, does an avatar or a stock photo work as well as photograph? Do other biographical details work as well? And how long does this effect last?

If you're into anecdotes and theories that can help you explain, predict, and otherwise impress those around you, check out Lone Gunman, Overcoming Bias and Freakonomics .

Meanwhile, we're ready to casually cite the classic marketing/business/social science examples, such as the Add An Egg phenomenon, the Kitty Genovese effect, how a waiter's tip can decline precipitously based solely on the waiting-time for the bill (citation anyone?) and the Hawthorne Effect.