I checked Yahoo! Mail options and noticed they have an archive service. First, it lets you pick a mailbox to archive. Then it calculates how much space you'll need and how long the download is estimated to take. But first, it hangs. And hangs. And hangs. And then you can't access your Yahoo! Mail anymore. Whee!
Their automated customer care service says they'll get back to me within 24 hours.
Update: just got an automated email from them telling me to try a bunch of things. Too bad I've already tried them (refreshing, logging out and back in, closing the browser and relaunching, etc.). Next thing you know they'll ask me to reboot. I still can't access my email.
Update 2: email's back. Over two hours without email and not a single important email came in! (Ovid shakes his little fist). On the other hand, the test email I sent to it also didn't arrive, nor did it bounce. They better have queued up my email. I hate to think that it may be corrupted