Russian police have arrested a hacker who projected a pornography video on a giant digital billboard, sparking late-night traffic chaos along a busy Moscow road. The January 14 stunt caused one man to have a fatal heart attack and left commuters too stunned to move, reports say. Driver Alyona Prokulatova told the Associated Press she was "so shocked that I couldn't even shoot video or take a picture of it". The video showed a man and a woman having sex and ran for about 20 minutes, according to witnesses. The electronic billboard sits above Moscow’s Garden Ring Road, 9m-wide by...