This morning my desktop computer, which runs Debian unstable, wouldn't boot. After a couple of hours, I tracked the problem down to a misbehaving udev package (version 169-1). Downgrading to version 168-2 solved the problem.
Just for once, I wish there would be an actual global apocalypse, then I wouldn't have to worry about fixing my computer just because I need to do some work. But I'm not that lucky. ^_^