There are a number of film adaptations of the DC Comics Universe currently in active development right now (Wonder Woman, Justice League, The Flash, and so forth), pretty much all of which are part of the DC Extended Universe that was established by Man of Steel in 2013. However, there is one DC comic book movie currently in the works that, until further notice, doesn't belong to the DCEU continuity: Booster Gold.
Booster Gold is a movie about the eponymous, time-traveling DC comedy/action superhero that is being produced by Greg Berlanti: the co-creator of The CW's DC TV show universe that now consists of four TV shows (Arrow, The Flash, Legends of Tomorrow and Supergirl). It appears that Berlanti's big screen DC project is taking the next step forward, with screenwriter Zack Stentz having seemingly gotten started writing the Booster Gold movie screenplay.
Berlanti recently reveled that for now there is "no connective tissue" between Booster Gold and the DCEU films, meaning the former doesn't need to worry about fitting into the continuity of the latter - until further notice, anyway. As mentioned, Stentz (who has worked on Berlanti's The Flash TV show and co-wrote X-Men: First Class, Thor and the upcoming Power Rangers) has now indicated that he's developing the film's script too.
Stentz posted the following photo to his Twitter feed (marked "Today's writing inspiration") and seemingly made a reference to the Booster Gold character with another Tweet - saying "The coolest guy in the room is usually less interesting to write than the person who thinks he's the coolest guy in the room."
Created in 1986 by DC writer Dan Jurgens, Booster Gold was the first major new superhero to be introduced to DCU continuity following the events of Crisis on Infinite Earths. Initially designed as a satirical take on the idea of the superhero-as-celebrity, Gold (real name: Michael Jon Carter) is a disgraced former football star turned museum security guard from the Gotham City of the 25th Century. Discovering a time machine, he travels back to the 20th Century, where he aims to use his knowledge of historical events and futuristic technology to act as a superhero - though unlike other heroes, he eagerly embraces media attention and commercial endorsements.
The character gained his greatest notoriety as a member of Keith Giffen and J. M. DeMatteis' late-1980s revamp of The Justice League; which broke with prevailing superhero trends of the day with an emphasis on humorous team dynamics and comedic-adventure storylines. There, Booster was frequently teamed with fellow technology-based hero The Blue Beetle (Ted Kord, the second iteration of the character created by Steve Ditko who served as the inspiration for Watchmen's Nite Owl); a pairing nicknamed "Blue & Gold" by fans.
Booster Gold is currently without a release date.
Source: Zack Stentz