Not tech related, but I saw this on the American Dialect Society’s e-list and thought it was interesting — and scary. Please, dear Gopod, do not add this nightmare illness to the laundry list of ailments that already assail me, your humble cyborged servant:
If you don’t know what a cluster headache is, thank God or whomever or whatever you believe in. Clusters differ from migraines in that, in the case of the former, there is no aura, no increase in sensitivity to light and sound, no nausea, and no throbbing. A cluster headache is just pure, unadulterated pain that has to be felt to be believed. In any case, here is the tiny vocabulary of cluster headache-specific jargon:
Clusterhead: a person who suffers from cluster headaches
Cluster headache: a kind of pain that beggars description, generally affecting only one side of the head and face
The Demon: the personification of cluster-headache pain
The Dance: one’s physical reaction to cluster pain, whatever that may be
Shadow: a kind of premonitory pain that tells you to get ready, because The Demon is about to strike
Fun, loose-brained 
Jamie, Adam, Grant, and others in the MythBusters posse are