I once bought a folder at an antique shop solely to get the roll of film in it (they wouldn't sell it separately). Nothing of enormous interest on that one, just a couple of exterior shots of someone's house.
But I once bought a box of IR sheet film that must have been from the late 40s (it said "Develop by June 1950"), and it turned out to have a couple of exposed sheets in it. (I *think* they were undeveloped, but of course I didn't see them until I'd put them through development myself and they didn't have anything like the images I'd tried to shoot.) They were pretty decent, apparently shot with a Speed Graphic or something similar (you can see the bed in one shot); one is the courthouse in Vancouver, WA, and the other is a semi-rural landscape from somewhere in the Portland/Vancouver area. The rest of the box appears not to have been used---I developed a few additional sheets just to check, but they were blank.