A California man was stabbed in the neck for asking a woman to silence her cell phone.

The man had gone to see the film Shutter Island, but was bothered by a woman talking on her cell phone during the movie. He complained to the woman, and she left the theater with a pair of men. These men came back after a few minutes and stabbed the victim in the neck with a meat thermometer! The man was hospitalized with serious injuries, and the two suspects still remain at large.
(source)