Trackballs That Can Spin
By Xah Lee. Date: . Last updated: .
trackball designs that allow the ball to
spin.
Here's idea using air bearings:
True Spin Balls
As far as i know, only these 2 truly spins.
ITAC Mouse-Trak Trackball
DT225 Trackball
Trackball Spin Test
L-Trac Trackball