Some years ago (about the time I was starting to read ebooks) I finally got around to cataloguing my paper book library - built my own database for the purpose. It tracks most of the common metadata (title, author, series, genre, first published etc.) along with details of the edition(s) I have, page count, scan of the cover, description of its condition, cover artist etc..
I also added last-read date, description, spoiler, review, notes and a 1-5 rating. I haven't tried to track such things as author's country, though the database does include a separate place for notes about the author, which I usually write up when the author is added.
And since that time I've been keeping it up to date as I go, including my ebooks. Writing up a description and review in brief (I push myself to be brief) I have found to be an interesting exercise, as well as useful in retrospect. Since starting this database I have often been surprised at how my memory of a book differs from what I wrote at the time.
My 1-5 rating is mostly based on how likely I am to re-read a book. 5s are favourites to be revisited regularly, down to 1s that I consider were a waste of time the first time.
There's enough in the database that I could track lots of things, but the mostly I just use it to look back over recent reads, or books I'm thinking about re-reading. I also keep track of books I want to get in this same database. Sometimes I use it to count have many book I've read in the previous year. But that's about it.
I like this thread. It's like a support group for compulsive behaviour.
