I enjoyed them together in last night's episode. I love how they both thought they coined the term "The One". And I mentioned it in the ep thread, but I really like how they turn to each other for the serious issues.
I just saw the ep where Jack tries to help out Tracy's baseball team. It was pretty funny. Not as funny as the other two we've been talking about, but still funny.
I'm pretty sure it was Rosemary's Baby in season 2. That was by far my favorite Alec moment in this whole series. Don't get me wrong, I love a lot of his other scenes, but that one was just incredibly hilarious.