I haven't posted in a long while as I maanged to get my TOS under control. I just wanted to post this in case anyone searches for it.

Out of the ergonomic trackballs, thumb trackballs, foot mice, mice, vertical mice, finger mice and roller mice which I tried (and spent over a $1500 on)
this cheap touch pad I bought off ebay

http://www.ergonomictouchpad.com/

was far the best. No shoulder movement or muscle activation is required. Its awesome. I hold it in my right hand and just use my thumb to navigate.You will need to speed the pointer up a bit. Works for macs too

Hopes this helps someone

yeah someone else rec'd that too me, i really need to buy it. i cant click a mouse at all, i have to use a marker to do it

its amazing to me all the "ergo" mouses and not one of them took into account that buttons are bad for you

Looks very interesting, thanks for posting the link.

So far i've been using the RollerMouse and a pen tablet - but it still hurts.