An internal bee hive! An internal bee hive!
Argh! It effortlessly combines claustraphobia and the nameless dread of "I'M COVERED IN BEES!!!" in one handy package that kids can climb over and, you know, try to smash with their sticky little hands or tap repetitively to anger the winged monsters within.
A neat way of keeping the kids amused, the adults scared and the bees at a psychopathic level of irritation that one day will spill over into ugly, ugly violence and destruction.
Manchester Museum used to have one of these until wiser councils prevailed and the whole thing was burned, dropped into a hole, sprayed with glue and cement and poison and locked up forever.
Also see the poem:
"If bees stay at home,
Rain will soon come.
If they fly away,
Fine will be the day"
I suggest adding the following:
"If anyone throws a rock