Onus
Titan
I am genotypically left-handed. Fortunately, left-handed people are more likely to be ambidextrous, as I lost much of my left-hand coordination when I became open-minded in 1980. I've never wanted to use a left-handed mouse. When I'm remoted into someone with a leftie mouse, I just carry on with the right hand, remembering to switch the clicks. I use a mouse in Guild Wars and other non-FPS titles, but prefer a trackball for FPS as there's never any running out of surface. I just can't pull off fancy jump moves, but I've never worried about it.