I sometimes fix friends & older family members computers as a favor and I've noticed that they usually don't really have any files anyway. I always make a backup before reformatting them and usually it includes their bookmarks and maybe 2-3 random files scattered in their 'Documents' folder, none of which are important. Their machines are more like just gateways to the internet than anything.
Through machines moves over the years I'm sure I have multiple copies of the most important ones anyway (keys, etc). If not oh well, life goes on. Shoulda made backups in the first place if they were that important to me.