Mathematics, as presented by Clifford Pickover, is a palace filled with awe-inspiring curiosities. His Math Book: From Pythagoras to the 57th Dimension, 250 Milestones in the History of Mathematics is a 500-page, full-color tour of mathematical highlights from 150 Million B.C. to 2007.
Each two-page spread has a fascinating story about a mathematical principle, discovery, puzzle, artifact, or person. It would make a great gift for people who dislike math because they "don't have a head for numbers."
Pickover does a excellent job of clearly explaining each topic, whether it's Aristotle's Wheel Paradox, the Sieve of Eratosthenes, the death of Hypatia (a mathematician "torn to shreds by a Christian mob" in 415 A.D., "partly because she did not adhere to strict Christian principles"), the Fibonacci series, the Goldbach Conjecture, Benford's Law, the Prisoner's Dilemma, Newcomb's Paradox, Tokarsky's Unilluminable Room, or any of other 250 topics in the book.
I have to get rid of most of the books that come in my door (I get several a day sent to me). This is one I plan to keep.