My laptop is only moderately recovered from a recent ‘spillage incident’, in that the arrow keys do not work very well and I need to replace the keyboard. But this cloud does have a silver lining. While the down key was completely broken, I was unable to adjust the brightness of my screen downwards (Fn+Down). During that time, my terrible (or terribly annoying) X slow crashes in which I progressively lose the mouse, the keyboard and sanity in various orders (because the main effect is the Ctrl key behaving as if it’s being held down, this last time I managed to scatter the same document all over my Desktop, since Ctrl and drag is copy in Nautilus).
And now the Down key is mostly working, I can adjust my screen brightness downwards… at the cost of needing to restart X every couple of hours. So, there you go. I might even be able to file a bug, depending on what ended up in the logs.