Don&#x27;t forget &quot;Gait DNA&quot;[0] for tracking your movement through a crowd, even when your face can&#x27;t be seen.<p>[0] <a href="http:&#x2F;&#x2F;news.bbc.co.uk&#x2F;1&#x2F;hi&#x2F;programmes&#x2F;from_our_own_correspondent&#x2F;6995061.stm" rel="nofollow">http:&#x2F;&#x2F;news.bbc.co.uk&#x2F;1&#x2F;hi&#x2F;programmes&#x2F;from_our_own_correspon...</a>