The photo above was originally from TubePrune's site and was taken by Donald McGarr.
"What really drives millions of Britons mad is simply, they normally only hear one side of the conversation. 'Conversations only work if there is a general agreement. There is a need to understand what is said and to talk back' said Professor Andrew Monk.
His team exposed 64 people (huge sample - WTF are universities doing?) waiting for a bus or on a train to a staged discussion - half on mobiles and half face to face - at different volumes. In all cases, the phone conversations annoyed volunteers more".