Got to work on time, which, considering the night I had, is really remarkable.
My external backup drive is telling me it isn't formatted and asking whether I want to format it. This is ominous. I am running WD diagnostics on it now.
My guess is that it's going to fail, if it isn't already dead and just echoing like one of those little memory things in SitL. This will be the third or fourth external drive I've had die in three years. Unlike the previous one to die, this one is at least a year out of warranty.
Oh, well, it gives me an occasion to go to the computer store, and I have presents to buy.