Several central banks are interested in cryptocurrencies because it allows them to devalue the currency from a central point. Cash is hard because it can be hoarded, therefore indirect measures are taken to devalue said currency.
“It is difficult to get a man to understand something, when his salary depends on his not understanding it.”
Seriously. You have an aging population causing consumption to decline, a global recession along the horizon, ever-increasing productivity replacing the need for labor, and you think your interest rates are going to a damn bit of good? We'll need to keep interest rates at 0 just to keep the whole thing going, forget about negative interest rates (which is going to cause a run on the bank and asset bubbles in commodities, real estate, anything else that can be a value store).
http://www.finextra.com/news/fullstory.aspx?newsitemid=27870
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