Using additional mouse buttons - possible?

[MadDragon]

The PC port seems to have been done by someone who never really used a keyboard+mouse setup. I'm currently unable to configure any of the mouse buttons to do any actions. Instead, I'm being made to use the arrow-keys and/or keypad.

I don't have 3 hands. One hand on keyboard (on the WASD keys and peripherals), one hand on mouse... sorry designers, no hands left for the arrow keys.

Anyone have a solution to being able to map mouse buttons for actions? (ie: left and right mouse buttons - or even mouse wheel - to zoom in/out in shift mode?)

[MadDragon]

Current "less than optimal" solution is to reprogram the mouse buttons to output selected keyboard keys, then remap commands to match those keys. But that doesn't solve the problem of the scroll wheel "up-down", at least given the my current mouse software.