Brianna Wu, a prominent video game developer, says there has been threats against her life. In a panel at the South by Southwest conference held recently, she held up a picture of an Internet troll in a skeleton mask. This person, whose identity remains anonymous, sent Ms. Wu a message claiming he wanted to end her life by putting a drill to her forehead. She also stated her husband and dog were threatened as well. Ms. Wu, who works for the gaming studio Giant Spacekat, is not alone in these threats. Other women in the gaming community have faced similar online harassment, which, they say, goes far beyond name calling and violent threats. A half-dozen police officers milled about in the hours before the events started, scanning the crowds for any potential problems. Each session was attended by a police officer who sat at the back of the ballroom surveying the crowd and looking for unattended bags.