Some time back I wandered across this interesting time-lapse movie of a new way of demolishing a tall building — one floor at a time, with all the work done at ground level.
The ground level columns are replaced by computer-controlled mechanical ones, all the ground floor “guts” of the building are removed, and then the building is lowered by a level. Tear out the old “ceiling,” put the mechanical columns back in, and you can follow the same process on the next floor. And the next. And the next…
Aside from being fun to watch, this approach is billed as being easier on the environment since less debris is generated, and the removed materials are more easily recycled.