An uncontrollable urge to dance.
[After Taranto, a town in southern Italy where this phenomenon was experienced during the 15-17th centuries. It’s not clear whether tarantism was the symptom of a spider’s bite or its cure, or it may have been just a pretext to dodge a prohibition against dancing. The names of the dance tarantella and the spider tarantula are both derived from the same place.]
(Video: Hedwig & The Angry Inch.)