Sort of -- beware, spoilers for S02E11:
Felicity's freshman year roommate Meghan had a mysterious box,
literally. She would rebuff anyone who asked her about it, looked at
it, or dared think of touching it. When we finally found out what was
actually in the box [SPOILER ALERT], it was kind of disappointing, but
freaky in a way that foreshadowed J.J. Abrams' future career: the
"Twilight Zone" episode revealed that Meghan actually kept Felicity,
Ben, and Noel in the box and was orchestrating their every move like a
On a more serious note: I don't think it has ever been revealed.
Amanda Foreman (Meghan) didn't know:
From liddymack: Amanda, what was in Meghan's box?
Amanda: They never told me what was in it, but I thought it could be a
confession to a murder. If you look back, there are very few things it
could be. I thought maybe it was a false confession, and that's why my
dad freaked out. I heard people saying it was a dead baby. I thought
that was a little gross and over-the-top.
In that same conversation, JJ dodges the question:
From Kim: JJ, what was in Meghan's mystery box? Make something up if
you have to.
JJ: We sort of dealt with that in our Twilight Zone homage in an
episode titled "Help for the Lovelorn." The prop itself is in my
office--I have yet to look myself.