Easily fixed: I submitted new address change cards using (at the postal clerk's advisory) the address I'd been using for the last six months and my corrected address. Didn't need to make a note of the mistaken address at all.
Fine and good, but Postcrossing isn't just about receiving mail--it's about sending, too, obviously. There's a mail slot in my apartment building's bank of mailboxes, a slot crudely gouged out of the slender aluminum door, captioned with the taped note "OUTGOING." But this slot is barely big enough for a business envelope and can in no way accommodate a postcard without folding or mutilation. Spindling's not necessary.
If I visit my in-laws at their senior living apartments, they have a perfectly adequate mail slot in their postal foyer. That's not always convenient, though, since my wife and I are against owning a car. It would be cheap to rent an Hourcar and visit them for a couple hours, and cheaper still to catch a bus (though the trip down there takes nearly an hour, and an hour back... if we leave while the buses are still running), but seriously?
Seriously? That's the best I can do if I want to send a letter?
Actually, no, I can do better. A very casual Google search turned up two mailbox locators, where you type in your city/state or your ZIP code, and they turn up results for mailboxes in your area.
The responses are entirely text-based, there's no image or pictures here. It would be difficult for me to picture the address locations of each box and I'd end up typing them into Google Maps anyway. Additional confusion ensued when I wasn't keeping track of which search bar I entered my information into. Type it into the one on top for the results you want. Entering it into the search bar just below it (the more obvious one, I think) and you get a bunch of Google results that come up in the Mailbox Locator display window. They don't look like the list of addresses you'd get ordinarily, but both kinds of results do show up after a full window of ads.
I love Google Maps, and I love data aggregators, so this will be the application for me.
Now, the only thing to see is how accurate this tool is. It looks great, but it won't mean anything if the mailboxes aren't where it says they are. And I'd go out and check now, only we're currently experiencing a two-day torrential downpour, so... I guess my postcards will just have to hang out with me a while longer.
UPDATE: I went out looking for the mailboxes in my area when the rain let up. Mailbox Map listed three mailboxes within a three-block area of my apartment. Walking to each site, I confirmed that none of these exist anymore. I suspect the same is true for those mailboxes a few blocks further out in any direction. I tried to look up mailboxes in Mailbox Locator and it simply did not have anything listed for my area at all.
Further UPDATE: Duh. USPS has its own collection box locator. I didn't even think of that. I'm not sure how accurate it is: I found three mailboxes through Mailbox Map and the USPS site doesn't one of the ones I found (again, by walking out to each location). It did list five in my area, however, and I can confirm the location of one of these.