Vampires.
But not in the sense of the typical "Hot Topic, emo, my life is so horrible I'm going to cut myself and then drink the blood cuz I'm hard core like that, but I wont' really because my mom says I have to be home by 9 and if she sees me with marks on my wrists she'll take away my ipod" kind of vampire way.
Vampires may have been over glamorized, however, that does not diminish the truly frightening aspects of them. And over the years, alot of the "common" ways to kill a vampire have been weeded out. For example, in the book "Interview with the Vampire" Lestat is asked if a stake through the heart would kill him, he responds by saying that that is, how we say, bullshit. Now with the Twilight series, the once tried and true method to kill a vampire (sunlight) has been weeded out. I can only think of one real way to kill a vampire. And that is too rip the body apart, burn the body then scatter the ashes.
I choose vampires because of the human aspect of them. Mainly because if I were presented with the choice to become one of the two, I'd choose to become a Vampire. I want my mind to stay as it is.