Alright, so it struck me the other day that whenever I meet an INTP (I suspect this might be a more general NP thing, though), they are invariably interested in music, film, literature etc. They know all the obscure stuff and all the classics, they are passionate about and devoted to their (self-chosen) hobbies and enjoy finding hidden musical gems and "self-improvement" through exploring the stuff they are into (if they aren't naturally into something, that's another thing altogether).
The INTP will constantly ask me "Do you know x?" "Have you heard y?" etc. To which I'll almost always have to say "No...". After a while, it becomes irritating and I start feeling like an undereducated fool. I don't naturally have the urge to get engrossed in such things in the real world...I do not seek them out and most of the fun/interesting things I've come across I haven't found because I was looking for them, but because they were suggested to me or brought into my life by other people (including school). I'm open to everything they suggest and often feel very grateful for what they've added to my life, but I don't purposefully go looking for it, I just pick up what comes my way...possibly because the INTJ's primary function is a perceiving one whereas the INTP's is a judging one. You pick, we accept.
So...then I was thinking...what do I do with my time when I don't really work very hard and don't inherently have the need to do anything *overtly* interesting either? Basically, I daydream and I think. As opposed to Ne which appears to need tangible creative input, Ni is fine sitting in a silent window-less room and running its course like that. The entertainment system lies within and is much less visible to other people, ergo, the INTJ might be seen as boring. Mac was asking me about Star Wars, to which I replied I have Star Wars in my head, but that really does seem to be the case.