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Declan wrote:

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Sandfort wrote: US postal regs end at the US border. The rest of the world is full of mail drops, accommodation addresses and mail forwarding services.

Or, even inside the U.S., you could run an anon mail-receiving locker (insert $20 bill for two days, much like train station lockers) service if you only accepted FedEx/UPS/etc. letters and packages. Obviously it would cost more for users, but for sufficiently valuable cargo...

This already exists, and has for many years (I have been using this service personally since the late 70s, early 80s. John Smith Suite (your drop box number here) 134 West 32nd Street New York City, NY