A range of interviews I've had in the past several wees prompted me to create a reference list of books and material every developer/architect should know. The list of material is available here.
A few books that I was really delighted with are Robert C. Martin's series - Clean Code: A Handbook of Agile Software Craftsmanship, and Agile Principles, Patterns, and Practices in C#.
All the material at the Books page is excellent and contains the core of what one needs to know in their everyday work. It is also a good refresher for people who have been focused on a small set of solutions and technologies at any given time. Happy reading.