Estonian geeks developed the code behind Skype and Kazaa (an early file-sharing network). In 2007 it became the first country to allow online voting in a general election. It has among the world’s zippiest broadband speeds and holds the record for start-ups per person. Its 1.3m citizens pay for parking spaces with their mobile phones and have their health records stored in the digital cloud. Filing an annual tax return online, as 95% of Estonians do, takes about five minutes. How did the smallest Baltic state develop such a strong tech culture?