Get on the website of a budget airline to book yourself a holiday and, while you are at it, fool around with the site code so that you can pick your own price. For tomorrow, show your workings. That is the kind of homework students on a new MSc in ethical hacking at Dundee’s University of Abertay might be set. Although, of course, the website they use won’t be a real one but a cod version for in-house use set up by a tutor – or even a fellow postgrad. Why teach these quite clearly criminal skills? Surely they could be misused?