One of the most basic forms of privacy is the capability to have a private conversation with another person, without having somebody else listen in. There are two ways to make that happen: You can be very, very quiet--closing the door to your office usually works. Or if you have no door to close (if you work in a cubicle, for example), you can try to vanish in the noise.
Sonare's Babble product makes the noise for you. The company's first product was a telephone babble-izer, designed to prevent coworkers from listening in to your side of a phone call. It records your voice from the phone, chops it up into random syllables, and plays it over a speaker in your cube, giving eavesdroppers a nice word salad to digest--all sound, no meaning.
The new upcoming version is designed for multiple speakers, for example, an open conference area. You point the babbling loudspeakers toward the people you don't want to listen in, and they hear random syllables on top of your own real speech, making eavesdropping nearly impossible. The phone product is $395 and available now. The conference-room version will be more, available this spring.