I have heard "non-denominational" Protestant churches identify themselves as such because they believe they are above the squabbling and blindness that characterizes denominational Christianity.
I have heard Christians identify themselves as "non-denominational" because they aren't really loyal to any particular denomination at the moment.
I have also heard from non- non-denominationals that "non-denominational" is in essence a denomination of itself, because churches of this identification are actually related in their origin, theology, etc. Is that true? Are there any distinct characteristics of non-denominational Protestant churches besides the name?