This sort of thing is fascinating, I wonder how much more usable undeveloped film is out there and what all is on it.
While not undeveloped, while cleaning out my late grandparents home a while back I found a box of color slides my grandpa brought back from WWII along with a yellowed list handwritten in German of the contents. They had apparently belonged to a German officer and contain a variety of scenes from rather dull landscapes to pictures of soldiers relaxing, some of tanks, trucks and planes. Pretty fascinating, I have no idea how my grandpa ended up with them, I didn't even know he was in the army until well after he died, he never talked about it when I was a kid.