http://bits.blogs.nytimes.com/2012/03/28/bizarre-insights-from-big-data/?_r=0

 If you buy a used car, your best bet is an orange one. Data scientists at Kaggle, a pattern recognition start-up in which Mr. Elbaz has invested, have matched previously separate data sets on buyers, colors and after-purchase problems. They figured out that if a car’s original owner chose an odd color, the car was most likely a means of self-expression. That self-identification raises the odds that the owner cared more than usual for the vehicle.

A few years ago I was speaking with the founder of an African mobile phone company, called CellTel. He told me that his company realized that they could predict the location of impending massacres in the Congo, because there were spikes in the sale of prepaid phone cards.

At first the company researchers thought that this was because there were more calls around the planning or fleeing of the massacre. In fact, the reason was that the prepaid cards were denominated in dollars, not the local currency. People, sensing impending chaos, wanted to have something valuable they could carry with them that was protected against local inflation.

- Traffic jams tend to propagate forward as well as backward. There is still no idea why this should be true.