As any celebrity knows, the lines dividing fan, superfan, stalker, and murderous stalker are often blurred; one day, you're receiving innocent, screwdriver-and-rock-filled gift bags, card attached reading, "Oh yes, we will be together, you and I. Mark my words," the next you're frantically dialing 911 to report the machete-wielding maniac standing over your bed and screaming something about never having received a thank-you note. Extreme Uma Thurman-enthusiast Jack Jordan, for example—currently on trial for having harassed the actress and her family obsessively for two years—isn't a stalker at all, his lawyer argues. He's merely your garden variety creep: