At the Lowes store in Gilbert, there is a kiosk in the paint department.
The computer in the kiosk lets you pick a picture of a kitchen, say, and the
pick different paint colors for the trim, walls and so on. As you pick
the different colors, the picture changes to the show the color you picked on
the trim or walls or whatever. It looks like a browser based application.
Anyway, my wife and I are playing with this and decide on a color
combination we like. It has a print button to get a list of your color choices on
a little card. My wife clicks print and a dialog box pops up to confirm
the destination printer. The dialog that pops up is obviously X-windows,
with the grey color and the "indented" box around the default button.
Sure, it could be any *nix running that kiosk but I'll bet it is a Free OS
such as a BSD or Linux. At least is wasn't Microsoft.