I have found some software called autohotkey that allowed me to easily remap the left windows key to be a mouse click. This seems useful with some repetitive tasks.
In the past, I have tried to make buttons from my spaceball act as a mouse click but could not get it to work. It also still does not work in conjunction with this software so I am going to try and remap a button through the registry to be a mouse click and then try and acess it through my spaceball.
I have also looked into ergonimic mouse and have found one called the evoluent vertical mouse that seems to help with this problem. 3m also makes a very extreme ergonomic mouse along with microsoft who ruined theirs by making it wireless and heavy.