My boss at my old job taught psychology courses at the school and incorporated a survey of our left or right brained characteristics into our employee evaluations. It wasn't the first time I'd done a survey of this sort, but it allowed me a little self-discovery at that point, especially because I'd been through a lot of huge changes since the last time I'd done any sort of personality inventory.
I discovered that I'm mostly right-brained: creative, yearning, imaginative. But my right-brained tendencies are heavily checked by the few left-brained characteristics I do have, which weigh rather heavily: analytical, love for the familiar, practical. I'm also (if it's not too self-flattering to say) a master of words and language. By this I mean that I may not always write with aesthetic mastery or even be interesting, but that I have a pretty good grasp of grammar, syntax, semantics, and vocabulary. However, the way I feel about syntax and semantics (and not so much grammar or vocabulary) is more governed by my creative, yearning, and imaginative impulses; I love examining the way that words placed together in different ways can have so much impact on the way we are perceived and the way we feel and I could really go on for ages about that.
I think everyone exists somewhere on a spectrum between the left and right brain; it's not a dichotomy by any means. It is interesting, though, that some characteristics will weigh more heavily than others and come in uneven doses, and that most people will find themselves leaning one way or the other.
Where do you see yourself in this spectrum? Have you encountered it before?
You can see the other illustrations done for this ad campaign here, along with the text in an easier-to-read version.