I am left-handed and I have fully adapted to the right-handed world. I can use scissors with my right hand (but not with my left!!) and I have no problems with door handles. I play badminton right-handed. Tin-openers, though challenging, are my friends. But--- I own a left-handed ruler and cheque books present me with huge problems. Fountain pens, though loved by me, cause chaos on my papers.
Here's my real question:
As a left-handed computer user, do you have any problems using your right hand to manipulate the mouse. I'm cool with both left and right (yeah! big tough me!) and often swap hands mid session. What about you? I'm up for a competition.