> tied together with serious steel cables, attached to the machines with some quite
> serious adhesive on a plate secured direct to the metal chassis of the machines.
I remember those well. You didn't even need a screwdriver. Just grab a computer and drag it across the desk, while letting the cable holding the plate back. A nice steady lateral force would slide the plate off the computer. It seems the makers assumed that thieves would only ever try to pull the plate away from the box. Uni students used to remove the plates this way purely for fun.