Jeff’s Trivial Spongeesque Mind?

To test Jeff’s claim to spongeworthiness, I ask him, and anyone really, this highly geekish question:  Of all the cases cited in the U.S. Reports, over centuries of U.S. Supreme Court decision-making, one case is cited more than any other.  Even Leiter has not yet counted this.  Jeff, name that case.

Hint:  it is not Marbury v. Madison. 

UPDATE:  Jeff gave up too early and Frank Snyder got it, in the hand grenade sense.  I’ll leave the answer for the Comments just in case you stumbled on this.

–Alan Childress