Passengers leaning their head against the window will "hear" ads "coming from inside the user's head", urging them to download the Sky Go app. The proposal involves using bone conduction technology, which is used in hearing aids, headphones and Google's Glass headset, to pass sound to the inner ear via vibrations through the skull.

"Tired commuters often rest their heads against windows. Suddenly a voice inside their head is talking to them. No one else can hear this message."

Oh hell no