THE COLLISION BETWEEN BASEBALL AND BAT involves an exchange of energy lasting less than 2 milliseconds. Whether the encounter results in a homerun or not (a subject of great interest this year as two players are swinging for the fences at a record clip) depends on the speed of the pitch, the speed of the bat, and the impact point of the bat. But generally the batter will want to make contact near the "sweet spot," about 17 cm from the end of a typical bat. Hitting the ball there imparts the least amount of vibration (and pain) to the batter's hands. Rod Cross of the University of Sydney (r.cross@physics.usyd.edu.au, 011- 61-2-9351-2545) has made a study of the sweet spot and found several surprises; first, that a baseball bat has two equally important modes of vibration and that consequently the bat possesses three sweet spots closely spaced over a few centimeters. And second, that there is no impact spot on the bat where impulse forces on the hands remain entirely zero. (American Journal of Physics, Sept. 1998; journalists can obtain a copy from AIP. Cross' website---mostly about tennis rackets---will soon display information about baseball bats as well.)