A friend of mine contacted me to share news of what he considered to be a remarkable coincidence. In an e-mail (liberally dotted with exclamation marks) he informed me that his wife goes to church with the sister of the UBS rogue trader, Kweku Adoboli. Crikey.
He was flabbergasted to discover that he was linked to the until recently jailed trader by a chain involving just three links. It is quite surprising but, in reality, not that improbable. In fact, as Microsoft uncovered when it investigated the flow of some 30 billion e-mail messages, everyone on the planet is probably linked to everyone else by just six steps. Indeed, I have just discovered that I am just four introductions away from the fraudster myself.
Although we are all rather closely connected to the famous and the infamous, we are usually unaware these connections exist. Even when we know they are there, we still do not know which of our friends, relatives or co-workers is the first crucial link. The person on your left could be signposted Adele; the one on yourright, Donald Trump.
 To be exact, 6.8 steps.