We will leave behind FaceBook walls. 😐

I was thinking along the same lines recently, Steve.  Sorting my late mother's possessions, I came across some letters written by my great grandmother a few weeks before her death to my great aunt.  They were hurriedly scribed in pencil, just describing her daily activities, but they revealed such a lot about her, her relationships, and the times she lived in. 

Now letter writing has been surpassed by the transitory nature of emails and internal postings, there will be few such artefacts for future generations to treasure.  Sad.