1.   An infrared beam on a tracker near his computer bounced onto the silver dot and transmitted a signal that allowed him to manipulate his cursor and type.

2.   An infrared light source on your PC bounces infrared beams off the mouse.

3.   And in the digital version of whispering, some of the devices can transmit short messages to another device across the room via infrared light beams.

4.   At the low level of energy needed for networking, researchers say, infrared beams cannot hurt the eyes or anything else.

5.   At the observation post, an Air Force ground spotter was using an infrared beam visible through night-vision goggles to point the pilot toward the intended target.

6.   Can you imagine trying to line up the keyboard, computer, modem and printer so that every infrared beam accurately reached the appropriate receiver?

7.   If the door touches an object lying on the ground under the range of the infrared beam, the pressure sensor causes the door to reopen.

8.   In each case, no wires, no infrared beam and no little brother blocking the infrared signal.

9.   In those devices, the mouse bounces an infrared beam off a special mouse pad mapped out with a grid.

10.   Instead of a tiny rubber ball, this mouse uses an infrared beam to keep track of movements.