The USB Finger Optical 3D mouse is designed for the PC, notebooks or laptops. It is compatible with MS Windows 98/2000/me/XP/Mac OS 9 and above. It features a scroll wheel, left and right buttons and can be easily used on most surfaces. The only annoying thing will be having to type with it attached to your finger while it wobbles around. Still, for those who use the mouse more it could be handy for reducing RSI.
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Neat idea! It looks rather awkward, though. I agree, typing would be annoying. Still, you have to love the innovation.
There’s is a smaller mouse called Z-Nano.
It is a LASER mouse (1600cpi) and uses front and back clicking.
Looks easier to use than this mouse.