It's not quite a vertical mouse but it's a similar concept. With the help of a friend I created a vertical trackball, which has served me quite well for several years at work.
Take a Logitech "Marble Mouse", and attach (with wires, there must be a better way, but hey it works) a piece of wood shaped like a triangular prism, with one side of the triangle the length and width of the trackball, and the other sides a similar size. The effect of the piece of wood is that it tilts the trackball at a 45 degree angle. Reverse the mouse buttons, use the trackball with your index finger, and wallah, you have a USB "handshake position" pointing device for $30 or so, plus a little quality time with a table saw and pliers.
Slashdot Mirror
It's not quite a vertical mouse but it's a similar concept. With the help of a friend I created a vertical trackball, which has served me quite well for several years at work. Take a Logitech "Marble Mouse", and attach (with wires, there must be a better way, but hey it works) a piece of wood shaped like a triangular prism, with one side of the triangle the length and width of the trackball, and the other sides a similar size. The effect of the piece of wood is that it tilts the trackball at a 45 degree angle. Reverse the mouse buttons, use the trackball with your index finger, and wallah, you have a USB "handshake position" pointing device for $30 or so, plus a little quality time with a table saw and pliers.