The Silmarillion: I knew I should not have given it away...
Looong time ago, I read the Hobbit.
After that I read the Lord Of the Rings (though I admit skipping the appendices). Thing is, at the time I was sick. Had the flu really, really bad. So I remember reading it, but I had no recollection of it, other than some fragments.
A year or so later I tried reading the silmarillion, but I couldn't get through it. It was as dull as watching grass grow. A big part of it is that I had no recollection of LOTR so not much of it made sense, and also because it is written as a history, rather than a story.
Some time ago, I remember holding it in my hands when culling my book collection, and thinking to myself: face it, you are never, ever going to read it. You might as well give it away. And I think I actually did that, because I can't find it anymore and it is not in my inventory lists.
Only recently I re-read LOTR (after having watched the movies for the umpteenth time) and this time I worked my way through the appendices. And the more I read, the more I wanted to learn about the history of the peoples of middle earth. I finished the last appendix yesterday, and thought it would be a good time to dive into the silmarillion... only to discover that I can't find it anymore and must have given it to the local librarian (along with a couple hundred other English books).
:(
I guess I'll have to buy it... again...
It's a good opportunity to also buy 'The Hobbit' and 'The children of Hurin'.