Ben Goldacre's "Bad science" column in The Guardian features an example of coincidence and the overactive imagination run loose on a map of prehistoric British monuments:
[Tom] Brooks has proved, he explains, that there were keen mathematicians here 5,000 years ago, millennia before the Greeks invented geometry: "Such is the mathematical precision, it is inconceivable that this work could have been carried out by the primitive indigenous culture we have always associated with such structures … all this suggests a culture existing in these islands in the past quite outside our expectation and experience today." He does not rule out extra terrestrial help.
Matt Parker, [Brooks'] nemesis, is based in the School of Mathematical Sciences at Queen Mary, University of London. He has applied the same techniques used by Brooks to another mysterious and lost civilisation.
"We know so little about the ancient Woolworths stores," he explains...
From there follows an inspired illustration of coincidences in large sets of spatial data.
(via Why Evolution Is True)