The Pragmatic Programmer: I read this fairly early in my career and it shaped a lot of my views on software, technology and personal development. Must read!
Rework: Since I've almost always worked in an office so this book was an interesting read describing an alternate universe. Haven't tried remote work yet but some of the tenets in the book (especially about communication) are universal.
The Manager's Path by Camille Fournier: The title is misleading. Do read it even if you're not a manager. In the past, I've been skeptical about books on management. But this book changed that world-view. I've learnt a lot about managing a team from her. One of the few books where I had to sit with a pen & paper to jot down my thoughts and notes.