Heaven knows, they made ours.
Paul Wood was taking care of his mother-in-law in Oriente, Brazil, when he and his wife noticed some vampire bats biting their cattle (as you do). Concerned, he went searching for the creatures - but only found some fruit bats in the outhouse.
After rigging a camera to get some footage, he decided it would look better the other way up. A quick bit of editing later, the addition of some jaunty Latin music, and hey presto: a fascinating little video called The Bat Brothers!