The New Your Times has reported that her boob was exposed on screen for nine-sixteenths of a second during the 2004 Super Bowl half-time show.  It was eight years ago that Justin Timberlake removed the piece of cloth covering Janet's unmentionable but we are still in court about the ordeal.  This passed week a Federal Appeals Court decided to drop the $550,000 fine that was directed at CBS from the Federal Communications Commission.

Here is footage of the incident: NSFW