1. Madonna at the MTV Video Music Awards (1984)
Like a virgin? Not quite. When the burgeoning pop singer formerly known as Ms. Ciccone hit the stage in a lingerie-like wedding dress, fingerless gloves, and multiple crucifixes — the first of many signature looks — a star was born. Her bold tweaking of sexual mores may seem commonplace now, but to a nation of young women, it was a revelation.