From what we can tell, the driver of the truck in the video below was calmly driving along when his boat and trailer decided to blaze their own trail. We don't know if the trailer or the hitch failed, or if the rig simply wasn't secured properly, but the result is properly dramatic.
Fortunately, it doesn't look as if anyone was hurt in the chaos, though we're guessing both boat and trailer will need some substantial work. Let the video below serve as a reminder to check your hardware before hitching up.