You already have stones to sharpen your knives, I think they can be very useful for that purpose. I remember when my mother used to sharpen knives, she would run them over and over again through a stone wall.
Interesting that your father still keeps that camera, it must have great sentimental value.
Yes, I am probably down with the stones for now, but I hope to use them next summer for camping. The camera was pretty cool and a good memory from his childhood.