People have used fake elite status cards to skip security lines and a girl once cleared Turkish immigration with her unicorn toy’s fake passport.
British Airways used to promote their mobile boarding passes with Osama Bin Laden’s name on it. And you used to be able to generate your own boarding pass from a website, which some poeple used to go through security when not flying (a very bad idea — better to actually buy a refundable ticket, clear security, and then refund the ticket if you must have gate access).