If you were ever paranoid that your employer was reading your social media missives, imagine being the subject of some future student's grad school thesis. From tomorrow, Britain's six biggest libraries will be entitled to crawl and archive the web in an attempt to create the UK's official digital repository -- in the same way the sextet must receive a copy of every book, newspaper and magazine published in the motherland. The first crawls will begin in the next few weeks, and your drunken holiday photos could be accessible from terminals in the British Lib