I was sort of thinking about this too the other day. I'm left handed too, and I thought it would be nice to do things backwards, just to screw with all the right handed people. (I have a backwards clock, and it messes with them pretty badly. It's funny.) But I signal with my left hand, and my good brake is under my right hand. If I have to take my right hand off to signal or anything, then I don't have my good brake at hand (bad pun, sorry). Haven't some people converted to lever throttle controls or something? I bet you could rig that up on the left pretty easily.