Instead of using new technologies to preserve for ready discovery material that might in the past never have been stored, or deleting everything as soon as possible, we can develop systems that place sensitive information beyond reach until a specified amount of time has passed or other conditions are met.

The last refuge of privacy cannot be placed solely in law or technology. It must repose in both, and a thoughtful combination of the two can help us thread a path between having all our secrets trivially discoverable and preserving nothing for our later selves for fear of that discovery.

Attacks on Internet sites and infrastructure, and the compromise of secure information, pose a particularly tricky problem because it is usually impossible to trace an attack back to its instigator.

I don't know how much thought is behind it, but it seems to me highly effective the way that Facebook will let somebody tag a photo with a friend's name, then others who are a friend of that friend can perhaps immediately see the photo, and the friend, in the meantime, has a chance to wander back and un-tag it.