In my first job out of college we used linear programming to solve combinatorial auctions - two things I had no idea existed until I interviewed with the company. It was sort of the nexus between OR and econometrics.
Very interesting to learn there was one man who helped give birth to both fields.
There is a great story mathematicians tell about Von Neumann when he first met Dantzig. From what I remember, Dantzig goes to the chalkboard to explain the finer points of his simplex method and Von Newmann quickly grows bored and interrupts him by saying "oh that". Von Newmann then procedes to point out some deep insights that would only have been obvious to Von Newmann himself. Dantzig later recalls being left speechless by the brilliance of Von Newmann.
Very interesting to learn there was one man who helped give birth to both fields.