A few weeks back, I was standing at a Hornsey rail station (in the UK) which uses overhead lines, and particularly has a number of parallel rail lines, all close to the platform.
While I was standing there, I went to hold hands with my girlfriend, and experienced a peculiar sensation in my fingertips, almost as if there were very large ridges on her hands. I've felt this before, touching a metal bodied laptop computer that was seemingly not earthed - dragging my finger across the surface my finger felt as if it was jumping along the surface, despite it being a smooth aluminium surface.
Is this a result of the overhead lines inducing a reciprocating current through my arm and/or fingertips? Is there some other feature of the railway that could cause this effect? And were we in any danger of any sort?