Dyson House
I spent much of my first year in Sheffield in Dyson House, the Hallam's old Business School. That was over ten years ago and it was an unpleasant hole even then. Its only saving grace was that I used to miss frequent lectures by getting stuck in lifts. They're knocking it down soon (its sister building has already gone). It's clearly the right thing to do as the building is vile but I'm already feeling misty eyed nostalgia for the place.