My bookshelf has been all fiction for about 6 years now. Technical books are more or less obsolete, the only ones I can remember buying in all that time is the Samba administrators guide from O'Reilly (useless.) and Stuart Cheshire's Zeroconf book (delightfully written, I could read it for pleasure but no help at all in really getting to grips with Zeroconf from an implementer's point of view.)

I still have some classics which I refer to from time to time. The camel book in particular, since there exists no better reference to Perl's core APIs. However, for anything else the web is a far better reference library.