I have a 07 Xterra and every time I turn a corner it sounds like there is a ping pong ball that rolls to the side behind the glove box. Is there a reason for this or was someone a practical joker at the factory? BradX

It's probably the key for the locking lugnuts the dealer installed for you. Wrap the key in a sock, muffles the sound quite nicely.

Or when you slammed the door shut, something you store in there fell out and then behind the box. Has happened to me before.