[Leica] Pointing device alternatives? "Pen?"

[Peter Klein <pklein@2alpha.net>]

Folks:  Does anyone use something other than a mouse for their computer 
pointing device?  After a few weeks of using photo editing programs and 
Sibelius (a music notation program I recently began using), I have noticed 
that the mouse is often not accurate enough for what I want to do.  And 
also that after a session of intense mousing, my mouse hand feels 
strained.  I've already had surgery once for a repetitive motion injury, so 
I would like to find an alternative that's kinder to my hand.

I've tried trackballs before, but find them no real improvement.  I'd be 
interested in trying a "pen" type device.  Does anyone have experience with 
a "pen" device on the computer as a mouse substitute, particularly with 
Photoshop or something similar?  I'd love to hear your thoughts, plus any 
contact information for the device, address, Web URL, distributor, etc.

Thanks!
- --Peter Klein
Seattle, WA