Trackballs
I've been having wrist problems recently, so I decided to try a track ball. I've bought a Logitech Marble trackball. It has a track ball and four buttons — two main ones, and two smaller ones which can be bound to different things. The secondary buttons did strange things by default (operating back and forward history in Firefox, and Mouse 4 and 5 in Emacs). So I ended up installing the Logitech drivers to rebind these. Very annoying. As well as mouse drivers it insisted on installing Music jukebox and a desktop E-Bay shortcut! This has to be the most irrelevat co-install ever. The drivers are also annoying; the GUI removes the "pointer trails" options which I generally use and always binds a click on both the main buttons to something, rather than just letting in through to the underlying system, thereby blocking cygwin's middle mouse emulation, for example. I managed to recover this situation with a bit of judicious registray hacking. Pointer trails can be turned on here, and the allowable gap for recoginition of a keychord can be turned down. But, really, should we have to go to these lengths?
Still. my intial experiences with the track ball are good. My wrist already feels more comfortable; it's largely static during mouse use. My accuracy still leaves something to be desired, but it not far behind mouse use already. Hopefully this will improve in time which will mean I can turn up the speed somewhat as well. For those with stiff wrists (oh, er, Missus) a trackball is recommended.