I thought this highly amusing tip of the hat to Firefly/Serenity was worth sharing, especially since it came from an article about something in the Fantasy genre rather than Sci-Fi. Skip all the way down to the bottom of the dev journal if you aren't interested in reading about class implementation in the fantasy MMORPG "Heroes Journey".
Here is a direct quote of the interesting part:
Well, that's it for this journal. I hope you enjoyed it, and remember: the design's always changing. So if next week we've decided to turn Serenity into our inspiration and replaced the Ranger class with "Space Concubine" and Summon Companion with an "Explosive Incense" ability, then just be comforted in knowing that I did mention spaceships and Newtonian physics.
(This is my first time posting a story, so if I fudged something up, many profuse apologizings!)