I've taken various tests on this.
I'm typically Neutral Good, and this gels with reality -- I'm very much Neutral Good.
My priority is that the "greater good" is done, that people can be content with their lives and function well. I don't like to hurt people and shy away from that, nor do I steal or take advantage of people; I respect their personhood and want to liberate who they are.
While I grew up in a Lawful atmosphere, at this point in my life I realize a lot of discontent and frustration with that is that I'm not Lawful myself. I'm ambivalent to Law. If it serves a relevant purpose, then it's useful and then I'll support it; if it doesn't serve a useful purpose, I usually ignore it or sidestep it.
Having had at some points in my life to become an enforcer of law and structure, I found myself agonizing over some aspects of such responsibility, especially if I was in conflict with those who were more Lawful or more Chaotic. I believe in that rules are necessary in groups due to the sheer diversity in behavior, so without the rules the group will likely fracture and people will also be hurt / taken advantage of (which, as a Good person, is a big deal to me); however, my preference is for people to monitor themselves when possible and have as few restrictions as feasible to create the most cohesive and productive environment. Overall, I prefer to be an example rather than an enforcer/cop.
Anyway, order and structure is just a tool. I'll use it if it makes sense. If not, I'd rather get rid of it. The more strict the structure gets, the more I find myself rebelling; however, I find the more chaotic something becomes, the less efficient and productive it becomes, and I don't like that either.
.... Sometimes I can veer closer to Neutral in my Good/Evil compass as well, although typically I always remain on the Good side. It's more that in this world, I am capable of viewing good and bad as parts of a cause/effect chain (i.e., detached rather than so personal), and bad things can create positive impact by how a person rises to meet the bad. I have a large sense of Balance, so I can grasp why someone might end up being more pure Neutral in outlook; yet I'm aware that if something personally bad happened to me or those I love, once it's made personal, it's hard to be neutral about it.
I got Neutral Good.
50% Good and 28.2% Lawful.
Pretty much what I would have expected except I might have thought I'd be more lawful!
I suppose it's more of a battle between the inner Intuition and the outer Fe Structure. I think there's a flexibility in Ni that isn't found as much in Si.
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I don't think I understand why Marm came up as Chaotic Neutral, though. Out of anyone on this site, she seems to constantly be defending the downtrodden and sticking up for the rights of others, passionately, more than I know I verbalize... yet I have no doubts that I'm "Good" in terms of what I value. That doesn't sound very neutral to me.
EDIT: Okay, just went back and read all your posts in the thread about it. So it seems like you're more a range of behavior, and what you say makes more sense to me now. Interesting comparison between you and JTG, and I'd have to say I felt that kind of tension when I was modding ... between Law and Neutral (him and me, respectively). I like to have the rules as guidelines and for general application, but I hate slapping people into Procrustean beds, and I'm too quick to see nuance, which makes it hard to apply rules like a cookie-cutter solution. (It's not even that I want to "help" people; the nuance itself demanded that I tailor everything to the situation at hand, to be accurate, or I'd feel like I was being "incorrect" in some way.) Some people appreciated that; others did not; oh well.