Flaming jump ropes seem like a cool idea, but it's one of those things that when it goes bad, it goes really bad.
Take for instance this poor woman who just wanted a cool video and a cool story to tell her friends. Instead, the two blokes on the each end of the rope are horribly out of synch, leading to the delivery of a flaming rope to the woman's chest, causing her to catch on fire.
Stop, drop and roll! That's what the sand is for!