To have so many contacts that you have to figure out how to keep track of them! I wish!!
That said, I would never trust any electronic medium as my only source of important files, no matter how many copies. In the end, form my limited knowledge of computers, it seems we are inevitably trusting something over which we have no ultimate control.
Print, print, print, and put copies of the really important stuff in someone else's house, or 2. I have recently taken old family pictures and put them in two different kinds of places in my computer, one on yahoo. But I still have the original photos, and printed copies of them.