I used FreeDOS once to run ancient software which controlled an industrial size oven. The client was having an ever increasing challenge of sourcing IDE disks (in 2008) so I was contracted to find a solution.

Eventually we settled on industrial PCs, solid state media and FreeDOS.

It was significantly cheaper than replacing the oven at £1M each.... in 50 of their factories worldwide.

Lots of solid state to IDE adapties out there too. But great example.