Well there are currently four volumes of <i>TAoCP</i>, so I guess I'll drop Volume 2. I can't see myself ever even contemplating implementing a number system or pseudo-random algorithm from first principles.<p>Not that I am likely to implement much of the other three volumes. They're top because they remind me of how many sigma I am away from the long tail of CS.
"The C Programming Language" by the Dynamic Duo
"Structure and Interpretation of Computer Programs"
"Design Patterns" by the Gang of Four