Most Likely To Appear: Two weeks after we've all forgotten about the thread

All email threads are not created equal. Some are lively and interesting, while others are boring and barely worth a half-assed gander. Whatever the case may be, one thing is certain: All email threads eventually die. It's an inevitable part of life (yes, even on the Internet). And yet, just when you thought you buried a heated back-and-forth exchange in the cyber graveyard, someone resuscitates it, weeks after its expiration date. It's puzzling, too, because you can't help but wonder: This person must have gone back through hundreds, maybe thousands, of emails to find this thread just to add some useless tidbit of information. Wouldn't their time be better spent in other ways, like working or creeping on Facebook?