A news anchor in Australia recently had a laughing fit at a REALLY unfortunate moment in her broadcast.
She started giggling at something her co-anchor said . . . and it was right before she had to talk about violent protests in Brazil and a collapsed building in Mumbai that killed five kids. She ended up apologizing later in the broadcast.
(Search for "TEN Newsreader Has Laughing Fit." Her "serious" report starts at :58.)