My work is pretty bad.

We have a box running windows 3.1 hooked up to an instrument on our plant. The answer I got when I asked about it was it has a proprietary ISA DAQ card in it with 'flaky' drivers' that prevents us upgrading it.

It's a non critical instrument but is providing 'useful' data I think its some type of microwave radar measurement instrument - very specialised hardware. It's been working well since the 90's so not worth spending money until it fails.

"Proprietary hardware cards" are notorious in industrial control system world they inevitably lock you into some ancient infrastruture when modern hardware and O/S's stop supporting ISA slots and things like that.