[1] http://pragprog.com/book/btlang/seven-languages-in-seven-wee...
The Cuckoo's Egg, Clifford Stoll. A really nice description of his process to understand the system, and why something was wrong, and the progress to catching hackers.
Myself, I love slim books that are high density yet well written. The C Programming Language by K& R and The AWK Programing Language by Aho, Weinberger and Kernighan are good examples. These books are just a joy to read.
If you ever need to give a presentation or write a report that uses any graphs or charts, this book gives simple guidelines that makes the visual information as clear as possible.
It talks about what to do, in your life as a programmer, and how to approach it.
EDIT: http://www.codinghorror.com/blog/2004/10/a-pragmatic-quick-r...
It's not really a programming book, mind you. It's a collection of stories that shaped the evolution of early home computer hardware and software.
It is one of the most challenging and inspiring technical books I have ever read, covering macros in great depth.
Read it recently, now consider it required reading for hackers