The road to greatness starts at an early age, and a children's book dedicated to introductory calculus will put your kid on the right path. Has a Nobel Prize winner ever credited Green Eggs and Ham for their success? Exactly.
Written by Omi M. Inouye, a programmer and admitted average math student, Introductory Calculus For Infants follows a couple of characters as they discover the 'wonders' of calculus. I'm going to go out on a limb here and assume this book isn't the best tool for SAT prepping, and probably would not have helped improve my abysmal math capabilities in high school.
In fact the dedication page asserts: "This book is for entertainment purposes only. the author is not a professor and is not qualified to teach anyone anything." So while your toddler probably won't be ready to apply for Harvard once you finish reading it to them, the $11 book at least helps give them an early appreciation for math and the idea that crunching numbers can actually be fun. [ThinkGeek via Laughing Squid]