I experimented with knife throwing as a consequence of writing Absinthe and Flamethrowers. It's quite entertaining and I've been recommending knife throwing anyone who'll listen (well, almost anyone.) It's much different experience than, say, throwing pub darts. To me, one really can't compare the bold, red-blooded flush of satisfaction derived from a perfect, cold steel stick in a target with the rather dainty, epicene feeling one gets when tossing a dart. It's harder to learn, but once you get the hang of it, it's a terrific.
Knife throwers, as portrayed in popular culture are usually strange and menacing; from crazy Bill the Butcher in Gangs of New York to the murderous twins Mischka and Grischka in Octopussy, to Rookwood in V for Vendetta.
I did some research on knife throwers in the media - invariably they're portrayed as weirdos.
How strange are they? Behold just a few a of the movie summaries I've gleaned from Internet sources having knife throwers as their focus:
The Unknown (1929) : Alonzo is an apparently armless knife thrower who uses his feet to encircle Estrellita with blades. Estrellita falls in love with Alonzo (she fears men's arms), so he goes to a hospital and has his amputated. Meantime Malabar cures Estrellita of her fear of men's arms, so Alonzo tries to have him killed during a circus act.
Santa Sangre (1989): A young man is confined in a mental hospital. Through a flashback we see that he was traumatized as a child, when he and his family were circus performers: he saw his father cut off the arms of his mother. Back in the present, he rejoins his surviving and armless mother. Against his will, he "becomes her arms" and the two undertake a grisly campaign of murder and revenge.
Mad love (1935): An insane surgeon's obsession with an actress leads him to replace the severed hands of her musician lover with the hands of a knife murderer which still have the urge to throw knives.
The Flintstones (1962): Fred becomes suspicious when Wilma's former boyfriend and circus knife thrower Rodney Whetstone shows up and strange things start happening.