I sometimes think 'I really prefer physical books, if only they had Ctrl-F' - but actually, in reality, it's often so much easier to leaf through and find something (from rough memory of where it was, skimming, jumping around, ..) than it is to search digitally (get the search term right, see results with little context, find it's impossible to search for part of an equation or the text in a diagram, or oh damn it was rendered as an image).