I have my eye on an errant limb dangling from a white oak by the fence. It seems to be attached to nothing from my vantage point (a second floor window), but must be be hung up on a branch at least 70 feet above the ground. I just hope that, when it falls, it doesn't take out part of the fence.
The small forest that used to grace the back of the backyard is now a few paltry trees. But because they are paltry they are precious. Even care and pruning can't stop the deadwood from falling, though. It's what deadwood does.