“I AM continually shocked and appalled at the details people voluntarily post online about themselves.” So says Jon Callas, chief security officer at PGP, a Silicon Valley-based maker of encryption software. He is far from alone in noticing that fast-growing social networking websites such as MySpace and Friendster are a snoop’s dream.

New Scientist has discovered that Pentagon’s National Security Agency, which specialises in eavesdropping and code-breaking, is funding research into the mass harvesting of the information that people post about themselves on social networks. And it could harness advances in internet technology – specifically the forthcoming “semantic web” championed by the web standards organisation …