My favorite of all time was my Calculus professor. He was (oddly enough) an ENTP for sure. I could follow his thought patterns and explanations amazingly, and he was really cool to joke around with (we waged friendly verbal warfare quite frequently).
Another was a Computer Science professor who I'm fairly certain was INTx (probably INTP). He was one of the most experienced and interesting guys I've had for a teacher, and he really took an interest in you if you showed interest first. I came to his office one day to shoot the breeze about a certain CS topic, and he ended up letting me borrow a bunch of books on the topic that he had lying around, and then going to the graduate library with me to find more stuff. I've never had a professor who was that willing to help a student out. He was a funny guy, too.
What about you guys?