I'm left-handed but use my right-hand for my mouse and left-hand for joysticks (back in the day). For the Wii I use my right-hand for golf and tennis but my left-hand for bowling. The main reason for using my right-hand for the mouse is to be able to use other computers, which was an issue as school - it wasn't worth the hassle changing it round every time.
And what hand do you use to open your front door?