I suppose this also applies to other wars since then, but WWII came to mind because it was just such a huge operation. Any information about other wars is also welcome!
I probably should not post as I am not a historian, however I know that in the Philippines a large number of Jeeps were sold/given to Filipino locals, which were then modified to result in the ubiquitous Jeepney. These can STILL be found all over metro Manila as well as out in the provinces. This probably violates a number of rules and I can delete this if it causes any problems (wikipedia, personal experience).