[lbriner]

Inversion of control. An idea that could be quite easily implemented by national postal services who already have a database of all addresses.

Instead of an address, you basically use a "PO Box number", which is an opaque handle. When you post it, it goes into the Royal Mail/USPS or whoever and they translate the PO Box into an address and deliver it to you.

Someone still has your address but the post office already have it so it's not much worse.