Over the last few days it is possible I have become fixated on Bitcoin, a cryptographically controlled virtual currency that presently exchanges at around $800 per. By “presently” I mean this morning. If you are reading this in 2014, odds are the value of Bitcoin has done something surprising, as the chart above suggests it might. Bitcoin has been extremely susceptible to market fluctuations since its creation in 2009. Part of that volatility owes to Bitcoin’s gradual acceptance as currency; until 2011, Bitcoins traded for exactly zero dollars, because you couldn’t use them to buy anything. Now, though, several legitimate retailers accept Bitcoin, and so do a lot of illegal ones.