Bitcoin – a currency run by a peer-to-peer online network, rather than any single organisation – has powered its way into the public consciousness.

Adverts for brokers appear on London Underground; major investment shops such as IG and Hargreaves Lansdown now offer ways to buy, and a deluge of emails encouraging people to invest is flooding the nation’s inboxes.

Some believe it is a new order of finance that will turn traditional banking and economic control upside-down. Others invest simply for fear of missing huge returns. Many use bitcoin and other “cryptocurrencies” for criminal gain.

In a major step toward making bitcoin mainstream, on Tuesday Chicago-based CME, the world’s largest exchange operator, announced it was preparing to offer bitcoin “futures contracts”.