DEFCON is the world's largest hacking conference, held in Las Vegas, Nevada. In 2012 it was held for the 20th time. The conference has strict no-filming...
Been there several times over the past decade. It's still great, but the sheer size of the entire thing nowadays means you spend more time in line than actually listening to talks. I'd still love to go once my employer starts approving travel again (post pandemic), because it's still a fun experience at the end of the day.