I'm left-handed for most things, though reasonably ambidextrous. I play all sports right-handed, except for racquet sports. Oddly enough, my right-handed brother is left-handed for sports. Weird family. I can write with the right, but it is rather laborious. I predominantly type right handed though.
I used to smoke right handed entirely, probably cos we drive on the left here, so I was flicking ash out the window. Also left my left hand free for other things, like drinking
I
vape left-handed mostly. This is so I wouldn't accidentally throw my e-cig out the car window when I started
vaping 
and just to make the psychological change from smoking (recommended by a psych to help give up smoking. Little did we know I'd just get addicted to
vaping 
).
My husband is totally lefty, can't do anything right-handed. Daughter total righty.