We were talking recently about several residents of Harrison Township, Michigan, who woke up this past Valentine's Day to find their houses, vehicles and property covered with a "mysterious, black oily substance". There was a lot of initial speculation that perhaps it came from the aircraft utilizing the nearby Selfridge Air National Guard Base.

Nope.

It was bird poo, as deemed by the Michigan Department of Environmental Quality. Residents say the mess was epic; some say it's hard to believe that the magnitude of ick was deposited by birds, but that's the story.