Flight etiquette is a delicate thing, especially if you're flying in economy. It's no mean feat to spend several hours crammed like sardines at 40,000 feet and remain on civil terms with the people sat around you. Air rage is very real, and there are varying degrees of validity to whatever might set it off. In my book, somebody plugging in a flashing LED light on a red-eye flight is up there with the most legitimate causes for a tantrum.
It almost sounds like something too entitled to be true, but this is exactly what one woman annoyed her fellow passengers with on an airplane flying at a time when most would probably want to get some shuteye. When Twitter saw the video of this atrocious faux pas, nobody had anything good to say about it. It is hard to believe that somebody would bring such an item on a plane, but the human race is a wild species.