There was a rumour about a Jew from the Soviet Union who tried to escape it with a LOT of money which he most certainly would lost during Customs check out. He did energy a trick to avoid this HUGE money loss by holding a party where an American Embassy stuff was invited. During this party he has completed a list of all banknotes in his possession. Got a signature from US Embassy stuff and simply incinerated all the $$$ he had in a fireplace. After escaping KGB officers who were much surprised to miss all the money with him he simply had left the USSR with those written witnesses and got his money from US treasury. Was that even possible and if yes, then I suppose that was real first case of digital currency which later came to form #Blockchain with all those #BTC , #ETH and whatever else used in today's life?