The Security Pass Hip Bump, which I first noticed a former client doing repeatedly in the library building she worked in, is particularly enjoyable. It occurs when someone carries their RFID-enabled security pass in their bag, and approaching a sensor, lifts the hip to angle the bag towards the sensor, creating a hands- free connection and activating the lock (the hands are often full of paper files, ironically enough.) It’s clearly an odd thing to do, when considered like this—to insouciantly cock your hips towards a small black rectangle on the wall as a form of greeting and personal identification—but can be carried off with a certain panache, admittedly.
When the same security passes are on extensible key fobs, they are articulated as if they were keys; when they are worn on lanyards, it’s as if they were simply identity cards from an earlier age, merely “shown” to a sensor rather than a security guard. This is different. It relies on a loose, instinctive, trial-and-errored understanding of the range of the radio waves involved, and the materials involved, and again feels like a form of interaction entirely unforeseen by the designers of security systems.
From here.