I figured out what it was that was most disturbing about the old building. Around the elevator bank in the center, where the bathrooms and the copy room are, the walls are this shade of pale yellow, completely unlike the white in the corridors all around. So there's this yellow block in the middle of the building with different lighting and a little corridor into it. It struck me -- this is exacly like the reactor core from Descent! The reactor was always set off by itself in this special part of the level, the walls were a different color, and something about the layout was exactly like the layout of that part of the building. The only thing missing was the red balls of death flying at you when you got too close. It'd definitely have made going for a drink more interesting.