While hockey isn't top on my list of favorite sports, I will have to admit that few things in sports are as exciting to me as an OT hockey playoff game, where there's no stupid tie (or regulation tie, ugh) result, you have to score to win, and it doesn't matter if it takes an extra 5 periods to do so.
Baseball is great because there's no "rigid" scoring system. If the bases are loaded, depending on where (or if) he hits the ball, anywhere for 0-4 runs can come in.
Football is football. I can't say why, but I just enjoy it.
Basketball I can take or leave with the exception of the Final 4 tournament.
Even soccer has been an enjoyable watch in the past on occasion for me, but only when it's European soccer/World Cup and when viewed in the company of foreign exchange student friends of mine.