What's a telemegaphone? It's a loudspeaker sculpture on top of the Norwegian Bergskletten mountain; you call a number, the telemegaphone automatically answers incoming calls and projects the sound into the immediate surroundings - in this case across the fjord and valley. More info here.
Now, I really hope that there are criteria for what kind of messages are OK to howl out into the beautiful Norwegian nature. Birthday greetings seem OK; a McDonald's promotion does not.