I randomly stumbled upon THIS ARTICLE that points out fourteen of the best of 'em while I was researching fonts for a special project today. As an added bonus, it also introduced me to the nifty website said article was published on, Comics Alliance.
I only own the first two seasons on the show on DVD, but I have to say that I wholeheartedly agree with this list. That was truly a breakthrough show. It was a gateway to comics for many of us, it had a rich full orchestral score, and instead of aiming for a purely contemporary style, it offered a classic and distinct take on art deco. Brilliant.
You know what else? The show holds up really well. Even today. What's your favorite episode?