Oh god, I was rewatching the end of Season 3 with a friend tonight...and I couldn't stop laughing when Olivia & Sam talk about the "box".
Olivia: What's in the box?
If any of you have seen some of the Lonely Island's stuff... you'll know why. If not, find it on YouTube. "Lonely Island - **** in a box" You won't be able to sit through that scene in Fringe without laughing. Ohhh man.... it hurts, laughing too much.