I second The Practice of Programming. I was also forced to read Pragmatic Programmer for a class in school, I was happy to find that this review sums up my thoughts perfectly about that: http://www.amazon.com/review/R3KBSGSQDBND0N/ref=cm_cr_pr_per...

Another commenter mentioned SICP, I'd add Let Over Lambda and On Lisp which while I haven't read cover to cover I've enjoyed every section I've read so far...

In the end I don't really agree with the author's conclusions that we shouldn't recommend books we haven't read at all. Passing on recommendations of others is defensible--after all, if someone asks for a recommendation they usually want one, not a response of "I don't know" or "Go do your own research!"