Ask HN: As a CS professor, what books should be in my office?

I recently moved into my new office as a professor and would like recommendations for what books I should keep on my shelves (they're completely bare at the moment). My research is in the human aspects of software engineering, but I am particularly interested in books outside of my specific research areas since I probably already have them.

So, what books should every [computer science] professor have in their office?