Day 12 - An episode you've watched more than 5 times
Let me say first off that I'm a serial rewatcher. If I've only seen a particular episode of a beloved show once, it was probably not a good episode. Hell, I can name several episodes of beloved shows that aren't good episodes, yet that I've still rewatched. But this question, I believe, is trying to get at "An episode that you go back to again and again, regardless of other factors." And I certainly have one of those. There are three gimmick episodes I never get tired of: the rashomon, which I've already talked about, the time loop, which I cannot actually think of a good example of right now, and the musical episode. Lord above, the musical episode is always my drug of choice. So no prizes for guessing that my answer to this one is "Once More, With Feeling." If there's one thing Joss can do, he can make something epic and spectacular as long as it's in the short term, and nowhere does he do it better than he did here. OMWF is just as grand as any musical film, and it manages to hit all the same beats as one in a time-constrained form. And even though the musical episode is one of the few gimmicks where I'm more than happy to just let it stand without justification or explanation, I love the way that there's a perfectly reasonable (well, by the standards of that 'verse) cause and a diabolical effect (even if I will never believe that Xander really summoned the demon), and that the entire thing is actually relevant to both the characters and the larger plot arc, crappy though that arc may have been. Overall, it really is something to sing about.