I've been keeping a daily journal for about three or four years now. About 20 of them are in storage back in Texas. When we moved to England in February 2007 for a three year stint, I started numbering my books, beginning with UK #1, of course.
I finished UK #11 today. It's always bittersweet to finish a book. The old one is a dear friend, after all. The new one? Well, there's the fear of the ultimate blank page. But I find that as soon as I make my first mark, ahhh. That's better.