On October 31st 2008 Satoshi Nakamoto, a pseudonymous cryptography buff whose real identity remains a mystery, unveiled a project he dubbed bitcoin, ‘a new electronic cash system that’s fully peer-to-peer, with no trusted third party’. Six-and-a-half years on, interest in bitcoin has waned. After spiking at $1,100 in November 2013, its value has dropped to just under $225. (http://econ.st/1LnwmMg)

This week’s theme: Money