Check this out!  Arne Hess has another video and this one gives us a look at Samsung's Optical Joystick.

Unlike previous Windows Mobile smartphones, the SGH-i780 isn't featuring a traditional D-Pad but this - as Samsung calls it - "Optical Joystick" or "Finger Mouse" which is a kind of 4-way touchpad. In addition to use to it to navigate, it also acts as the action button to start applications. If used in the 4-way navigation mode, it emulates a standard D-Pad while, if used in the mouse mode, it shows a mouse pointer:

Check it out here at the::unwired

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