Everyone who wants to be an airline pilot should read
Fate is the Hunter by Ernest Gann. It's essentially the autobiography of an AAL pilot from about 1935 to about 1955. The technology has changed, but the people...I've flown with or met every character in that book.
For those of us who learned
and taught at FlightSafety or Embry-Riddle or what not,
Stick and Rudder by Wolfgang Langewiesche is an excellent book for washing away a lot of the super-technical B.S. we dealt with. It reminds us that if you pull back, the houses get smaller, etc.
The Probable Cause by Robert J. Serling is a great book about airline safety, and how many of the systems we use today came into being.
The
Air Disaster series by Macarthur Job contains excellent summaries of some of the more important airline accidents of the last century. Very educational.
And, although it's not an aviation book, I urge everyone who wants to be a good captain (or leader in any field, for that matter) to read
The Caine Mutiny by Herman Wouk. The book (
not the movie) caontains some of the best object lessons in CRM I've ever come across.

Happy reading!
P.S. If you enjoy nautical fiction, check out David Poyers "Dan Lenson" books.
The Circle and
The Gulf are quite good.