Science fiction fandom other groups including LGBT communities, libertarians, neo-pagans, and space activist groups like the L5 Society, among many others. Some groups exist almost entirely within fandom but are distinct and cohesive subcultures in their own rights, such as filkers, costumers, and convention runners (sometimes called "SMOFs"). Fandom encompasses subsets of fans that are principally interested in a single writer or subgenre, such as Tolkien fandom, and ("Trekkies"). Even short-lived television series may have dedicated followings, such as the fans of Joss Whedon's "Firefly" television series and movie "Serenity", known as Browncoats. Participation in science fiction fandom often overlaps with other similar
Dream On (Glee) On" was filmed in March 2010. In October 2009, Michael Ausiello of "Entertainment Weekly" reported that 20th Century Fox, the studio behind "Glee", had approached Joss Whedon about directing an episode during the show's first season. Series creator Ryan Murphy is a fan of Whedon's work, and praised the musical episode of his series "Buffy the Vampire Slayer", commenting: "Joss directed one of the great musical episodes in the history of television on "Buffy", so this is a great, if unexpected, fit. I'm thrilled he'll be loaning us his fantastic groundbreaking talent." Whedon deemed "Glee" his favorite television show, but