Start-Ups Seek to Help Users Put a Price on Their Personal Data

Facebook’s pending initial public offering gives credence to the argument that personal data is the oil of the digital age. The company was built on a formula common to the technology industry: offer people a service, collect information about them as they use that service and use that information to sell advertising. People have been willing to give away their data while the companies make money. But there is some momentum for the idea that personal data could function as a kind of online currency, to be cashed in directly or exchanged for other items of value. A number of start-ups allow people to take control — and perhaps profit from — the digital trails that they leave on the Internet.