If you're a right-handed person, is it possible to efficiently teach yourself to write with your left hand (or vice-versa), or is this hard-wired into our brains at birth?

I'm curious about teaching myself writing with my left hand as a side-hobby.

its perfectly possible. i've taught my left hand to write. unfortunately it'll only write backwards unless i really concentrate.(its actually neater than my right.)

I've made only slight progress, my letters are still overly angular, and it seems to be easier to write with a pencil.. but eh. I guess it's going to take a year or two to write as well as my right?

it took me two months. you'll get there eventually. just write 3000 copies of the alphabet and you'll get there.