Shortly after I moved to the San Jose area to take a job running a small non-profit association (not SF/F/fandom related) in 1994, I opened at PO Box at the Sunnnyvale post office. Now that I'm a full time Nevadan coming to the Bay Area only a handful of times a year, and now that I've had years to transition all of my "real" mail to the address in Fernley, it was time to shut it down. Conveniently, I had to be here in the area on a weekday during the month that the mailbox rent would have otherwise automatically renewed.
I opened the mailbox one last time and removed the accumulated mail. I'm sure that the box clerk will be happy that I'm gone, because when you only collect your mail once every few months, the box is generally pretty crowded, albeit mostly with junk mail.
I turned in my key and got my deposit back, signed some papers forwarding what little real mail I still get here on to Fernley, and that was the end of an era.
That PO Box was also the mailing address for Worldcon Intellectual Property, the small non-profit corporation set up by the WSFS Mark Protection Committee to hold legal title to the WSFS service marks. (This was necessary before registering the marks in the EU, because the EU Intellectual Property Office doesn't understand the concept of an unincorporated association.) I've never been completely comfortable with this setup because it was a single point of failure. Fortunately, SFSFC (which shares two directors with WIP) has its address just a few boxes down from here, and agreed to be WIP's new mailing address. Therefore, there are multiple people who can get at the mail (not that WIP gets much real mail) and no more single points of failure. Along that same line, I took the opportunity while driving down from Sacramento to stop at the bank where WIP's bank account is located and officially change the mailing address. While we do all of our banking online, we should keep the address updated. And a few weeks ago, while renewing routine paperwork with the California Secretary of State's office, I changed WIP's mailing address as well. All the necessary organizational stuff is done, and I am relieved that it's resolved.