This has been a very enlightening thread. Thanks everyone for sharing. Since we are pretty much all INFs here, I'm going to allow myself to get alittle 'airy-fairy' and long-winded.
I can sometimes intuitively visualize emotions, almost as if they were physical objects. It's really hard to explain.. the best I can do is to describe them as having a string-like consistency, and usually they are intertwining with other emotions, rapidly moving along and 'slippery'. It's as if I could grab onto them to feel them, but never really be able to fully grasp them. Emotions don't always have the same feel, look, color, or brightness. They move with various speeds, some intertwine less with others, while others actually bend and fold upon themselves in insanely complicated pretzel like patterns. (The latter I tend to associate with INFJs.)
Sometimes I don't get the 'string-like' feeling at all, but something more akin to a rock. My ISTJ grandfather was like that; a huge but impenetrable pile of emotions.
My intuition is used largely to extrapolate and imagine possibilities. How would this person react to such and such? My intuition becomes greedy and wants to explore. I end up asking alot of questions if someone really interests me, or if I want to understand the emotion better. Metaphorically, I am reaching a hand out to 'feel' the emotion. It's all about studying and learning about what's going on underneath the surface. I'll even go as far as to create a archetype of someone in my head, and ask it questions, because for some crazy reason it actually can help me understand some things better.
My thinking and detailed oriented side come into play by analyzing and experimenting with details in the real world. It's probably the side of me that makes me ask people questions I already know the answers to, simply to see how they word their responses, or to see if they are lying. Once they answer, I put a check on my clipboard, and move on. How did they react when I challenged an idea? Did they maintain eye contact, lean in closer or pull away? *checks clipboard* They laughed just alittle bit too hard at that joke. *makes a note to explore this later*
I often find that I pick up certain details in the moment, but don't add them up until later when I'm reflecting and digesting everything. Then, suddenly, I realize that the person was probably lying to me, or that the girl was actually flirting with me. Oops!
One final thing... INFPs can be very good at pretending to be other types, I think, because of our understanding of emotions. For example, ESTJ emotions often come across as sleek, shiny, hard, and thin to me. Oftentimes sharp, too. If I were to take the bundle of my emotions, and straighten and stretch them out a bit... perhaps set a couple of tangles off to the side, I can approximate ESTJ bahavior for a bit. I force my skin to become a bit thicker, I go into the situation knowing what I want, and I psych myself up a bit to do more social interaction that I normally would. Eventually, though, I tire out and go back to being my normal INFP self.