Tangential, but I watched a video about maintenance on the Russian high speed train, Сапсан (sapsan), and when they started the train for a test the unmistakable sound of Windows XP starting was heard. It could have been for any number of systems on the train, but I found it funny. Admittedly it was US documentary, and they really butchered the translation for dramatic effect, so I wouldn't be surprised if that wasn't fabricated also.
most ATMs used to be backed by a mainframe.
I saw some newer ATMs using Windows Embedded so I guess they changed at some point.