Yeah. Protomyth made the point about aggregating biometric data with other data (shopping, akin to the Target pregnancy notice letter, browsing, etc.). That could be effective, if the sensors and social media, shopping, other data were available.

I know everyone (or most people) get hunches about what's going to happen by observing other people's behavior. Whether it was predicting a break-up, guessing that someone was pregnant, or in a new relationship. The glut of data available now would likely reveal a lot if we allowed it to be aggregated.

I guess I shouldn't have thought so narrowly about just biometrics (and heart rates, in particular).