I do recall seeing on at least one occasion (a friend's parents' dining table, circa 1986) a widget into which you pour oil and vinegar, and out of which you somehow magically* pour oil&vinegar. Does anyone know what these are called? And do they really work? Or is the fact that they don't the reason I only recall ever seeing the one?
I also think I've oil and vinegar on the table each in its own small bottle with a pour spout. Is that the normal presentation?
* I remember the pater familias explaining how it worked, and it making sense to me at the time, but it was a long time ago.