I'm going to a very different route than my colleagues: Sandman by Neil Gaiman. It's a series of graphic novels which delves deeply into theology, philosophy, and the human condition. Since it's in the form of a graphic novel, it's much more like "reading" a TV miniseries, and makes for a great introduction to Neil Gaiman's writing style (which will take you straight off the deep end into the fantasy genre). They're also easier to pick up and set down as the whim strikes. If you really enjoy the setting, the Lucifer series of graphic novels takes one of the most interesting characters from the setting and expands upon it. It was adapted to a TV show as well, much to the chagrin of anybody who actually enjoyed the graphic novels.
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