You may never fall asleep again in a train
"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."
Can you imagine someone who's a bit mentally unstable leaning up against the window, hearing voices and flipping out...
It being Sky Deutschland, I presume by "trains" they mean Deutsche Bahn
. It's not clear have they agreed to this (but it does sound like a done deal). I can imagine if it does happen, that the little transmitter will have to be well hidden, otherwise it will be a target of annoyed commuters, bored youth, and of course, anarchists.