Code Complete by Steve McConnellis, in my opinion (and many others), the best book ever about the art and discipline of coding. Basically, it's just the bible of how to design and build quality software. So, I'm really looking forward to Code Complete 2 (link is to a draft manuscript of the book) - if you've never heard of this book or read it, do yourself a favour, set aside a few hours and read the draft - then buy the book when it comes out in June. As a measure of just how good the original is - it was published 10 years ago, yet many people still consider it the bible of coding!