I just lost some untold number of hours of work. It looks like our back up disk for Time Machine has been unplugged for a few weeks. During which time a book I was working on seems to have completely disappeared. I did evetually find a version of it I emailed myself (as a cheap backup) a few weeks back. I'm not going to think about what used to be in it. About how it used to be a lot longer.
I'm just going to be glad that I have it at all.