Had never thought about Firefly being Steampunk until someone pointed it out to me. They were a group out of their time. Space Steampunk. Ok, I am going on record to coin this new genre -- Space Steampunk.
I Love Captain Mal Reynolds! (a.k.a. "Castle", now) If you've never seen the Firefly series, with it's culmination movie, Serenity, then you have missed out on a ton of great lines as well as an epic story.