interesting...well, before I try to get the answer, I will try and name some factors that would determine what the cards would be...
1) You posted this, and offering your own money...which means that you
probably won...also, you told others about the hand, so it was either a really bad beat, or an awesome win...leaning toward awesome win.
2) Opponent is a tight player (from your description), was in the BB, and called your raise, which would mean he had to have
some kind of hand. Also backed-up from the fact that he lead out with bets, as well as called your all in
3) river didn't help him
4) you only raised the "usual"
I'm gonna guess:
you: pocket 6's
him: AK
unless...you guys tied with KJ, but I know how much you LOVE KJ
haha