Bitcoin hits $9K. Bitcoin is world’s 30th largest currency even with 4 million possibly lost forever. Coinbase is allowing margin trading. Editor’s note: margin trading is not a good idea for an unsophisticated investor, and this article is included as additional evidence of the digital currency mania. Another billionaire weighs in about bitcoin. I.C.O.s represent the most pervasive, open and notorious violation of federal securities laws since the Code of Hammurabi. I was unaware the Code of Hammurabi violated federal securities laws. Bitcoin futures. Is Elon Musk Satoshi Nakamoto? Doubtful, but it’s fun to think about. Ethereum 2.0. Notes on Devcon 3. Ethereum now handles more transactions than all other digital currencies combined. Mo money mo problems. Tyler Cowen on cryptocurrencies. Russia reverses its stance on digital currency. Unpopular ideas about blockchain.