When I write my first book of memoirs, I will use a photo like this one to help me remember all the stories of my childhood. There are so many that I couldn't hope to remember them all with out something like this to make them spring back to life.
Who ever the first person was to think of this is a genius. You can click on the photo to see all the notes that I've added so far. I may add more as time goes on. I have 17 so far, but each one of them could be several pages if I were to elaborate on them a bit.