You could move the mouse to the left instead; I've been doing that at work (but not at home) for ergo reasons: it's a shorter move from the home row to the mouse if the hand have to cross the number pad. It took about a week of cursing the ergo team, and then it's pretty much normal feeling. (Also some amount of cursing Apple because the reversed mouse buttons only work when i login, not at the login screen; and some amount of cursing mouse makers because very few models are nice for left handed use)