HANOVER, GERMANY - MARCH 16:  A sign in French that reads: 'We accept bitcoins' hangs at a display of the LedgerWallet Nano USB stick that enables security-protected transactions with bitcoins at the 2015 CeBIT technology trade fair on March 16, 2015 in Hanover, Germany. China is this year's CeBIT partner. CeBIT is the world's largest tech fair and will be open from March 16 through March 20.  (Photo by Sean Gallup/Getty Images)