Wow!
This thread is absolutely fascinating!

Being new to this MBTI thing (relatively new?), I've only just understood that there
is a difference between Ni and Ne (or that there were even different "classifications," if you will, of N).
Anyway, everything everyone has said is incredibly clarifying. The "thought processes" responses from the ENFP and the INTJ were especially interesting. I decided to do a little analysis on my own thought process as an Ni, Fe (as opposed to the Ni, Te) and it was interesting to compare it to Ne, Fi. There really wasn't a difference between my process and Ni, Te, but there was a definite difference between me and Ne, Fi.
It matched up perfectly with what everyone has been saying about how the Ni train of thought was more linear than the Ne, but that it was similar in it's way of connecting things. I also noticed what was already noticed (haha) that Ni draws more from past experiences, what it knows, etc. while Ne drew more from the surroundings and used that to fuel their thought process.
What I found was the most interesting, however, was that, while I did go off on a few tangents, I always came back to the original strain until I had come to some sort of "conclusion" with that strain (or what I felt was adequate enough to be called a conclusion). This goes back to the "linear" observation. OH! And this went along with the tangents, too. I followed one tangent until I was satisfied with it's "conclusion" before I went back to address the original strain.
Anyway...very interesting!
And I didn't meant to address the people in this thread as "the ENFP" or "the Ne" and "the INTJ" or "the Ni." I just didn't feel like spending time finding usernames.....but I'm sure you guys don't care
Edit: haha, I guess I should go further in explaining the difference between the Ne train of thought post and my personal Ni experiment. I feel like my reply was more of a "this is the Ni mind" when the title of the thread is concerned with the Ne mind. The Ne seemed to be sporadic in his (her?) tangents, while mine (and the other Ni) are more methodical, it seems. Reading the Ne's thoughts was awesome because it was SO stressful for me. Hahaha

I wanted there to be some sort of structure and resolution to it so badly and the only thing I could find were the common themes (the beetle, the water, etc.) It was great, though, because I have a number of really good Ne friends and the insight into the mind of an Ne really explains their actions so much better.
Anyway, the Ne is definitely less structured...it reminds me a little of a tornado that touches down, does it's thing, disappears into the clouds for a little bit (the equivalent of it "coming up for air" or being sensually grounded for a second to grab a glass) and then touches down in another location. I may still be carrying some of the remnants of it's previous touchdown, but it's in a different place. Touchdown is random, as well. Ne is simply not as concerned as Ni with follow-through and things "making sense". I think this is due to Ne's train of thought is fueled by external stimuli and Ni fueled by internal past experiences, knowledge, etc.
The external world changes constantly, so the Ne's intuition adapts to that and, thus, it's thought process changes constantly. Ni gets a stimulus and intuition evaluates it according to it's past experiences, it's knowledge, etc. Because those things have already happened or are already established in the Ni's mind, the thought process is more solid.
This isn't to say that Ne isn't capable of thinking things through to resolution (or that Ni isn't capable of leaving things open-ended and fluid), but it's just that they incline to the opposite way.