The Pragmatic Programmer
I just finished reading The Pragmatic Programmer (links on my Furl) and have nothing but good things to say about it. This is more than just a programming book: The Pragmatic Philosophy described could be applied to just about anything you do in life – they just happen to relate it to software in this book (as is to be expected from a book pontificating upon the importance of loose coupling). If you haven’t read it, I strongly suggest picking it up.