Your Favourite Tech / Eng. / CS book(s)?

chris_eineke writes: "I like to read and to collect good books related to computer science. I'm talking about stuff like the classic textbooks (Introduction to Algorithms 2nd ed., Tanenbaum`s Operating Systems series) and practitioners` books (The Practice of Programming, Code Complete) and all-around excellent books (Structure and Interpretation of Computer Programs, Practical Common Lisp). What`s your stocking stuffer book this Christmas? What books have been sitting on your shelves that you think are the best ones of its kind? Which ones do you think are -1, Overrated? (All links are referral-free.)"