Firefly: Ariel
Really great episode, from the intense opening scene with River and Jayne, to the awesome hospital heist (Including probably the most disgusting scene I've ever seen in a TV show), to the very emotional final moments. I absolutely loved it.
"The next time you decide to stab me in the back, have the guts to do it to my face."
Firefly: War Stories
I loved getting to know Wash more. He definitely is a really likable guy. This episode gave me a greater appreciation of the characters. I love it. Also, Book has to be one of my favorite characters. I definitely find myself relating to him (and Simon, too).
"No power in the 'verse can stop me"
Can't believe I only have 4 episodes and Serenity left. I'm going to miss this show.