I finally got around to Googling Markéta Irglová, who played "The Girl" in Once. It turns out, she's 19. As in, years old. As in, she's not old enough to drink legally in the U.S., and she has two albums out. And they're really good albums.
This is in the same category of realizing that when Mozart was my age, he'd been dead almost a year.
 Actually, Mozart was just shy of 36, so if I were him—utterly ridiculous, if you know me—I'd have died on 14 July 2006.