Thought provoking, if not always practical. Designing Web Usability By Jakob Nielsen A good book, but if you've read Jakob's site extensively, there's absolutely nothing new here. We bought this book for one of Idyll Mountain's employees as a reference. I liked this so much that I seem to have bought it twice, in two different versions. Here's the book that did them already, read up.
Comics blend images and text.
The web blends images and text. Read this book if you want to be a great web designer. Of course, not all good references are on dead trees. Here's a selection of web sites I use regularly. Cynthia knows all, tells all.