My mum is left handed but me, my father and brother are all right handed.
Saying that, although I write with my right hand, I have a lot of left handed tendancies such as eating. My mum eats the right handed way round though despite being left handed!?!?!
When I started to learn the guitar I started to play it left handed until my teacher made be learn right handed instead.
People say I wear my watch (right wrist) (left shoulder) and carry my bag the wrong way round though I always thought it was more personal choice.