I've grown up using right handed mice, and my current one is moulded specifically for right handers (it's the Logitech MX610). Saying that, though, I can use a mouse left handed the same as right handed. In fact, maybe better in some circumstances - I can't draw with a mouse using my right hand for toffee, but can left-handed. But I rarely need to, because I've got a graphics tablet.

I'm not much of a PC gamer, either, and what I do play doesn't bother me, whether I play left or right handed.

Scissors and can openers are complete bitches, though, and I'll tell you that for free.