Culling books is so hard. I'm a massive book hoarder. I love my books and although I hold alot of unread ones - I still continue to add on a weekly basis. I'm addicted.

You could always keep an inventory of the ones you're culling so you can always re-acquire ones you miss ? I know I have suffered from culling something and then a few months later think to myself... oh dammit I had a book on that very subject! or something like that!

I also try to keep a book journal (try being the operative word here), to keep record of all the duds and greats. :-)