A new concept of advertisement is literally putting adverts straight into people‘s skulls by using ‚bone conduction – the transfer of sound to the inner ear through the bones of the skull. Advertising agency BBDO is using a combination of the concept and clever technology to allow individual commuters to hear an advert in a noisy train carriage. The company is harnessing technology to allow train windows to silently talk to commuters in a new product placement strategy. Transmitters on a train route between Munich and North Rhine-Westphalia send high-frequency vibrations to windowpanes, allowing commuters to hear advertising messages through bone conduction. The messages cannot be heard by the rest of the train passengers expect the commuter whose head is in direct contact with the window pane. The sound transmission technology is currently used in some headphone and hearing aids as well as by the military.