in mainstream television, requiring science fiction series many episodes to resolve an ongoing major conflict. Science fiction television producers will sometimes end a season with a dramatic cliffhanger episode to attract viewer interest, but the short-term effect rarely influences financial partners. Dark Angel is one of many shows ending with a cliffhanger scene that left critical questions open when the series was cancelled. Media fandom One of the earliest forms of media fandom was Star Trek fandom. Fans of the series became known to each other through the science fiction fandom. In 1968, NBC decided to cancel Star Trek. Bjo Trimble wrote letters to contacts in the National Fantasy Fan Foundation, asking people to organize their local friends to write to the network to demand the show remain on the air. Network executives were overwhelmed by an unprecedented wave of correspondence, and they kept the show on the air. Although the series continued to receive low ratings and was canceled a year later, the enduring popularity of the series resulted in Paramount creating a set of movies, and then a new series Star Trek: The Next Generation, which by the early 1990s had become one of the most popular dramas on American television. Star Trek fans continued to grow in number, and first began organizing conventions in the 1970s. No other show attracted a large organized following until the 1990s, when Babylon 5 attracted both Star Trek fans and a large number of literary SF fans who previously had not been involved in media fandom. Other series began to attract a growing number of followers. The British series, Doctor Who, has similarly attracted a devoted following. In the late 1990s, a market for celebrity autographs emerged on eBay, which created a new source of income for actors, who began to charge money for autographs that they had previously been doing for free. This became significant enough that lesser-known actors would come to conventions without requesting any appearance fee, simply to be allowed to sell their own autographs (commonly on publicity photos). Today most events with actor appearances are organized by commercial promoters, though a number of fan-run conventions still exist, such as Toronto Trek and Shore Leave. The 1985 series Robotech is most often credited as the catalyst for the Western interest in anime. The series inspired a few fanzines such as Protoculture Addicts and Animag both of which in