The X10 RF Remote Control in the kitchen stopped working, which could mean only one thing: a set of dead AAA cells.
A negative terminal in the battery compartment showed the expected corrosion:
The corrosion evidently pushed the cell away from the terminal just enough to starve the remote.
The cells, on the other paw, looked just fine:
They’d been in there a year, sported a date code that’s still a few years in the future, and had a 1.3 V loaded output. Looks like that little bit of corrosion gave me enough of a heads-up to get the cells out before they rotted.