But I cannot possibly bring myself to throw away books. It's (almost) religious. Books are the foundation of civilized culture. The nazis burnt books and destroyed cultures (the things parents teach you..).
No I couldn't destroy them either. Also you have to separate the actual material in the book itself, from the dead tree that gets dragged around with it.
When I was honest with myself, it was purely the financial aspect that made getting rid of my books a difficult proposition. I gave away over a thousand euros worth of books. I kept less than 10 that I hadn't read yet, and will give them away once they are read. We kept a lot of my 2 year old daughter's books, as she doesn't have a kindle yet, but we didn't keep all of them.
Don't throw them away! The trick is to give them to a library. Win-win situation.