A long time ago, but not that far away, I lived in Norman, Oklahoma with two roommates.
One of those roommates, Burntout, worked at the mental hospital, a very stressful job.
Sometimes Burntout would roll a great big joint, grab a flyswatter, go out to the screened in porch and close all means of egress.
He would then proceed to smoke the joint, making sure to exhale in the general direction of the flies.
He would then go on a fly killing spree.
(Stoned flies are much easier to kill than non-stoned ones.)
This, almost ritualistic, act came to be known as Fly Hell.