I confess to being an out-and-out Luddite when it comes to bitcoin and other so-called crypto-currencies. To the extent that I think about them at all, I think that they are an ephemeral by-product of those creepy ‘virtual worlds’ in which obsessed gamers eventually go mad; that only such lost souls could seriously believe unregulated online money might eventually supplant the state-backed real thing; and that fashionable belief in them can only lead to fraud and loss.