3. Madonna - "Like a Virgin" (1984)
Madonna had a handful of hits before the 1984 MTV Video Music Awards, but her performance of "Like a Virgin" that night changed her career forever. Not many people had heard the song at that point, but when she came out in a wedding dress and began writhing around on the floor, all eyes were on her. She later claimed she had no idea the camera were zooming into her thighs, but it certainly didn't hurt her sales and it soon became her first Number One hit.