Although written for teens, adults will also enjoy all Eoin Culfer books. Culfer creates Artemis Fowl as a know-it-all super-smart ultra-rich kid who doesn't face the same limitations as us meer mortals, but this is in part to mock novels that really do create such characters in seriousness.
I love the tough Captain Holly Short and her drive to solve the problems herself, no matter how small she is. I also find the centaur computer geek hilarious.
(By the way, one pronounces Eoin as "Ian.")