When I was in college, some of us had to share our student post office boxes because there weren't enough to go around.
My box-mate was a guy who had flunked out a few years earlier and been granted permission to come back, so he was class of '72 or '73, even though we were into the late 1970s. (At my college, the class you matriculated with was your class no matter when you graduated. You actually had to get special permission to change your class year if you graduated in a different year from your official class year.)
So anyway, I'm a very naive little sophomore, it's Winter Carnival weekend and this *very hot* guy shows up at our (coed) fraternity house. I asked one of the other brothers who he was and was told "That's Jim K___. He's a '72 who's just coming back to finish his senior year."
Me: "Oh, I share my box with someone like that!"
Other brothers burst out laughing. I had no idea that "box" meant something besides, well, a box, post-office or otherwise.