I'm mostly ambidextrous, but there are quirks.
Although I'm considered right-handed, I can do almost anything with either hand, but do enough left-handed many people think I'm a lefty. There are just a few things I can only do right-handed and a few I can only do left-handed. I tend to eat with my left hand, but for some strange reason even I can't figure out, I eat desserts with my right hand. I can only use chop-sticks with my left hand.
Most of the time, I'll use which ever hand is closest for the task.