I(V) = kV3/2
Childs's law is a deeply obscure and now partially achaic physical law concerning the current in a valve-diode with anode voltage.
OK, so Childs's law is not a fundamental law, but a derived law, useful in a specific case and very few beyond. BUT Childs's law is a now the scientific equivilent of an endangered species, rarely seen in the wild this law is now limited to captivity. If we do not preserve and conserve this law in the few reserves still availabe it will almost certainly die out.
I am somewhat of a fan of Childs's law, and feel new use can be found for it, if only we try hard enough to find it a place in society where it can thrive of its own volition.