Love this, and have been thinking about it for a while (after having moved literally 10 times in 10 years). I picture something similar to OAuth permissions, where at any point I can revoke access to all or specific pieces of information to anyone.

As an extension (and this is potentially where the money is), I can think of an intermediary service (a-la Google Voice call widgets) that allows entities to contact me without ever giving away my phone/address/etc.