One of the most recognizable comic book characters, Wolverine holds a dear place in many a geek's hearts, particularly because Wolverine story arcs usually involve more than just heroes fighting villains. Well, to be fair, Wolverine storylines do typically come with a handy dosage of carnage and whoopa**, but these characteristics serve to enhance the plot lines and humor of Wolverine graphic novels. Logan, aka James Howlett to some, hails from a sordid past that even he remains a bit unsure of, which makes Wolverine a bit gruff around the edges. But when Wolverine stories break past his rugged exterior, they reveal a complex, damaged character whose inherent animal impulses force him to face as many personal struggles as he does external ones.
The very best Wolverine comics place this messed-up character into situations that challenge his moral abilities as much as they do his physical ones. Even still, usually Logan pulls through using a combination of physical prowess, a remarkable healing factor, and the fighting spirit of an actual wolverine. Better get out of his way, bub.
You'll also find a Wolverine story arc on this list of The Best Gambit Storylines in Comics.