"Wherever you are in the world, we'll know somebody in common - give me sixty seconds."

With that cheerful wager Welsh comedian Elis James begins each round of The Cymru Connection on BBC Radio 5 Live. A caller rings from Carmarthen, Cardiff or a Welsh exile in Auckland - or even Tokyo; they have one minute to identify a mutual acquaintance with Elis.

Nearly fifty years ago, my wife and I coaxed an ageing Hillman Husky across the Skye ferry to visit a remote distillery. Standing at the locked gates, we bumped into our Cambridge neighbours - 570 miles from home. Pure coincidence? Not quite.