Jennifer Lopez, 2000 and 2013
The singer took the Grammys' scandalous red carpet trend to the next level in 2000 with her ultra low-cut Versace frock. "I had to have it," she said of the dress. "Those fashion moments happen by mistake -- you can't plan things like that." Ignoring a dress code memo that was sent before the 2013 Grammys, Lopez flashed major leg in a super-sexy Anthony Vaccarello gown. "You inspired the memo," fellow presenter Pitbull joked on stage.