I'm not sure how to type this friend of mine. He's an IXTJ I'm pretty sure, just not positive if that X should be an N or an S.
His hobbies seem NT-ish on the whole: computer games, pen and paper RPGs, paintball, fencing, Star Wars, reading science fiction of all kinds. He's also into car tuning and racing. Professionally, he's a computer programmer. Sounds like an NT, right?
On the other hand, abstract kinds of ideas don't appear to engross him nearly as much as they do me. I mean things like psychology, philosophy, MBTI, discussing random hypothetical situations, etc. He'll talk about these kinds of things when I bring them up, but his mind seems to pull more towards the concrete, while I'll continue in an abstract vein indefinitely. Does this sound more like an SJ?