[User9821]

You give Amazon your ID number. They do a lookup on the ID when you place an order to receive the current mailing address. It would apply to everything, so you give all of your friends and family your mailing ID. Anytime they want to send you something, they run a lookup on the ID (enter it into a website) and get your current address.

It's similar to a website. If HN moves to another server, everyone doesn't have to update their bookmarks to point to a new IP address. Instead, they visit the same URL as always, and it automatically sends everyone to the new IP.

[icebraining]

I think it would only work if the USPTO was in on it, instead of forcing everyone to look up the address. It should still be publicly available (for the Amazon case, and such), but not required just to send something.