Karen M. recently referred to something as "emo," and suddenly I'm seeing the term everywhere. Turns out it's more or less derived from "emotional hardcore" as a genre of music, and so of course it now also refers to "a wide range of fashion styles and attitudes somewhat affiliated with Emo music and its related scenes," as Wikipedia puts it.
The musical term has apparently been in use since 1985 or earlier, so I guess this is still more evidence (as if we needed any) that I'm culturally illiterate.
I'm not normally a big fan of Urban Dictionary, but I'm amused by a bit of sample emo dialogue from one of their entries on emo:
girlfriend: C'mon, lets have sex.
boyfriend: I'm too sad to have sex.
girlfriend: I'm sad too; lets have sex and cry.
boyfriend: I'm already crying.
--from the definition submitted by "Pureblarney"
On a side note: "literally" alert! The Wikipedia entry for "Emo (music)" includes the phrase "members of a band would become spontaneously and literally emotional." As opposed to being only metaphorically emotional?