In a comment on this answer, TKR brought up an interesting point of grammar I'd never heard of.
Αἴαντε [Ajax-DUAL] is an interesting case. Though readers of Homer since antiquity have interpreted it as "the two Ajaxes", this seems to be a misunderstanding: it originally meant "Ajax and Teucer", an Indo-European "elliptical dual" (where dual of X means "X and someone closely associated with X").
This sounds interesting, but I've never heard of an "elliptical dual" before. How and when was it used in Greek? Clear, unambiguous examples (i.e. where it's clear it doesn't mean "the two X") would be especially appreciated.