The Magicians (Lev Grossman)

This trilogy is just a total blast. Maybe not for everyone, but it hit the exact sweet spot for me. As @Carly put it, the best way to describe it is "Harry Potter for grown ups." If that sounds like something you'd be interested in and you haven't read The Magicians yet, give it a try.

My favorite fantasy book. A reductive summary: Harry Potter for grownups.