Must Read CS Books For Self Self-Taught Programmers

In light of past discusion about Self-Taught Programmers vs CS-Educated Programmers:

What are must read CS books (or other resources) that help you in your daily work? (so I don't mean code complete or head first design patterns)

I'm a Self-taught programmer and I think I'm missing some knowledge of algoritmes and discrete math. but perhaps there are other great subjects/books (compilers etc)

EDIT: Thanks everybody for the great suggestions

EDIT 2: The list so far (unsorted)

http://sharetext.org/YUE