> IMEIs are very pervasive, carried around by 100's of millions > of people and generally not intended to be shared with the > Internet. my american social security card, which admittedly is a bit old, has "Not to be used for identification" emblazoned on it in red. for me, a seminal document was the 1973 "Records, Computers, and the Rights Of Citizens," a report of the secretary's advisory committee on automated personal data systems of the us department of health, education, and welfare, chaired by willis ware. it spawned the privacy act of 1974, and i still have my copy. see [0]. it warned of the use the social seurity number as an identifier. [interestingly, mitre (also chaired by ware) did a report for the air force in '68 which reccomended the ssn as an id] today, in the states, the ssn is the ubiquitous identifier, and a major target of identity thieves and may be second only to cross site cookies as the identity target of marketeers. in the mobile society, the ids of our devices are becoming identy gold, and should be transmitted with extreme caution and only under compelling circumstances. randy -- [0] http://itlaw.wikia.com/wiki/Records,_Computers_and_the_Rights_of_Citizens