If you do have broad shoulders however, narrower keyboards are rather painful to use. Right now, I'm using a Logitech G710+, which is a full-sized IBM-syle keyboard, with an extra row of garbage buttons on the left side. If my left hand is in line so it is comfortable and inline with my shoulder while on the asdf keys, my right hand wants to be half off the right side of the numpad. Makes typing left-handed and mousing right-handed very comfortable, but typing with both hands on the homerow somewhat cramped. It'd be interesting to try a keyboard that had the keys split apart so that asdf was in line with one shoulder and jkl; in line with the other.