There are a couple of stories which come to mind. Anne McCaffrey wrote one called Dull Drums about students auditing computer diaries and the like. Then there’s a story by Asimov or Clarke or someone of that era about all the computers of the galaxy being finally linked together. After the final link is made…
someone asks the computer, “Is there a God?” and the computer replies, “NOW there is.” and kills the person who tries to remove the vital link
There’s a similar story where someone distances himself from humanity to get closer to the computer system which now runs the Earth, because his speciality is complex networks and he’s found the weak point. As other humans teleconference in with the aim of telling him he’s ostracised…
he cuts the vital link, and reveals his plotting. He has now initiated he disabling of the computer and asks the others, “Well, that was what you wanted, wasn’t it?”