TrackPoint
Alternatively referred to as a style pointer or nub, TrackPoint is
a mouse solution used with portable computers that was first introduced by IBM in 1992 and is a small isometric joystick that resembles a pencil's eraser head and is located between the "G", "H" and "B" keys on the keyboard. This technology enables a user to keep their hands on the keyboard and still be able to control the mouse. The left and right buttons for this mouse are commonly located under the space bar.
In the picture to the right, is an example of what the TrackPoint looks like.
Also see: J mouse, Mouse definitions, Touch pad