I was quite surprised to find out this afternoon that Windows 3.x was not a footnote in history for as long as I thought.  in fact Microsoft only finally retired it on Nov 1 this year!

It has not been available as a mainstream OS since 1995 and the advent of Windows 95 but has actually been sold as an embedded OS for cash registers and in-flight entertainment systems on Virgin airlines for example.

Fantastic stuff in my book.

BBC have an article covering the story here.