It shouldn’t take long before these technology-free zones become popular oases for a public that’s drifting more and more into a gadget haze and doing a reverse lookup phone number.  According to a 1982 Air Force review of biotechnology, ELF has a number of potential military uses, including "dealing with terrorist groups, crowd control, controlling breaches of security at military installations, and antipersonnel techniques in tactical warfare."  And the ubiquity of such technology today — especially considering the quantum leap in cell phone usage in recent years — only makes such concerns that much more pressing.  And even though satellite-based tracking technology exists, even fewer people are likely to consent to having their whereabouts tracked on a daily basis in the off chance that they might get lost on a back country road.