Microchips with antennas will be embedded in virtually everything you buy, wear, drive and read, allowing retailers and law enforcement to track consumer items — and, by extension, consumers — wherever they go, from a distance.

A seamless, global network of electronic “sniffers” will scan radio tags in myriad public settings, identifying people and their tastes instantly so that customized ads, “live spam,” may be beamed at them.

These are two possible future scenarios based on current developments in radio frequency identification technology.