Here are two of my favorite Serenity / Firefly wallpapers I have come across. I used the first (lighter) one for quite a while a few months ago. The second, darker one I just added a week ago when I firefly’d my computer all up. I added a ton of Firefly sounds and the Firefly wallpaper. Click on one to get the bigger version (Sorry, only have the huge and/or widescreen versions of these)