Before anyone hits that "Alert abuse" button, I've got several scanners programmed with railroad frequencies and, even worse, one equipped with crystals for railroad frequencies.

The man who invented trainspotting: It has become a dirty word, but why?

ALEX RENTON Sunday 21 November 1993

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And so trainspotters remain safe to laugh at. Exclusively male, they are, perhaps, the last minority group that can be reviled without fear of opprobrium. But perhaps not for much longer. The trainspotter, it was recently revealed, may be psychiatrically challenged. Dr Uta Frith of the Medical Research Council's Cognitive Development Unit, has said that trainspotters and other obsessive collectors of trivia, may be suffering from Asperger's Syndrome, a mild form of autism.

The syndrome, identified by a Viennese doctor shortly after the Second World War, is characterised by social ineptness, an over-literal and pedantic approach to language, a lack of sense of irony or humour and obsessively pursued hobbies - finding, as it were, safety in numbers.