There was a trend a few years ago where users would deactivate their FB accounts when logging out, so that people couldn't see/interact with them while they were away.

http://edition.cnn.com/2010/TECH/social.media/11/12/facebook...

So maybe that's not as stupid as it sounds. You could also have some level of caching, eg I visited your pictures yesterday so people can get it from me for some time if you're away.

I definitely see potential in this form of "distributed but controlled" storage mechanisms.

Similarly, I like the idea of having a local backup drive, and another copy at a friend's place (possibly encrypted).