This book is an intense hit of information. All the stuff I needed to know is here, without the flimflam of 'HTML - THe Definitive Guide'. There's very nice introductory stuff on broader technologies - like Flash and Real - although it will all be outdted before long, but then that's true of any printed reference.

If your a web designer, particularly if you code by hand or pay attention to different platforms, browsers etc, this is the ideal reference.