Somehow the hardest thing is to contentrate on doing everything with the other side because you tend to do stuff with your main hand without thinking about it. The hardest conquers were hand writing and using the computer mouse. The last one especially sucks when you got an ergonomic one targeting your main hand.
So I started getting common with it, except when gaming. For gaming I used the right hand. Cause none of the people would wanted to have played with me using my left hand, I guess.
It was a weird experiment but most of the things (where you don't need that much accuray) are handled by your off hand pretty fast in an acceplable way even if it might take some additional time.