Roland Piquepaille writes "We've been told for several years that RFID tags would eventually be everywhere. This isn't the case yet, but researchers at the University of Washington would like to know if the future of social networking could be affected by these tags and check the balance between privacy and utility. They've deployed 200 antennas in one UW building and a dozen researchers are carrying RFID tags on them. According to the Seattle Times, all their moves are tracked every second in the building. Of course, it can be practical to know if a colleague is available for a cup of coffee but this kind of system (if in widespread use) has some serious implications. As the lead researcher said, 'what we want to understand is what makes it useful, what makes it threatening and how to balance the two.'"