Comment Re:Introduction to Computing Systems (Patt/Patel) (Score 1) 517
This is a great intro book. Coming out of high school and having only programmed in C++, it was really useful as an overview of what is really going on inside a computer. It's a concepts-only book though; the assembly language and architecture are not used in the real world.
I took Patt's classes as well. They made all my other classes seem boring and terse in comparison - he really makes you think. His teaching style was very polarizing though.
Other useful books:
Hennessey and Patterson's Computer Architecture,
Raymond's Art of Unix Programming,
Rochkind's Advanced Unix Programming