Fact: I keep my uncooked eggs in the refrigerator (usually a good idea), in their original packaging, which is typically your standard cardboard egg carton. They never, ever, are kept in any other fashion.
Fact: I keep my hardboiled eggs in a bowl. They never, ever, are put in back in the egg carton. It's not even a temptation (though now that I think of it, it could save refrigerator space, like I have anything in there competing for space anyway).
Not Quite A Fact in the Scientifically Provable Sense: Approx. 85% of the time, if I'm hardboiling eggs, they're the only eggs in the house anyway because I'm trying to use them up.
In spite of these facts, everytime I make hardboiled eggs, I knock the egg against the counter to put a small dent in the shell signifying its hardboiledness. Pointless. Utterly. A carryover from my childhood when eggs mingled carelessly in the melting pot that was our refrigerator.