Attention Deficit Creator Disorder / Flip-Flop of God: Tarantino has a habit of publicly brainstorming out loud, and will often verbally bounce around ideas about movies but then rarely, if ever, mention them again—and then only to announce it probably won't happen. It's a common practice among Tarantino fans to take every one of his proposed ideas with a grain of salt until filming actually starts. Here's a list of examples:
He wrote True Romance and planned on directing it, but reportedly lost interest in the project, and it was subsequently handed over to Tony Scott, who took out Tarantino's signature nonlinear structure and aversion of Gory Discretion Shots, in addition to changing the Downer Ending.
Kill Bill Vol. 3, which would focus on Vernita Green's daughter being trained by a now-blind Elle Driver to get revenge on the Bride for killing her mother, which has never become anything concrete.
He's stated that he would like to adapt the novel Less Than Zero to film.
Inglourious Basterds was eventually made, but he had been talking about for over ten years in one form or another, including a miniseries, to the point where it became near-vaporware in Hollywood. He also mentioned a prequel in passing.
He considered splitting Django Unchained into two films like Kill Bill, but ultimately decided against it.
Killer Crow, a World War Two Blaxploitation film about black soldiers who make "a warpath to Switzerland" after being "fucked over by the American military," would have been the third chapter of a Spiritual trilogy that began with Django Unchained and Inglourious Basterds.
He's also spoken about doing an "earthbound" science fiction story that "wouldn't involve spaceships."
After The Hateful 8 was released, Tarantino has spoken about a number of ideas for his next project, including a 1930s gangster film set in Australia, a contemporary movie with "a cool driving montage," and "a really, really scary horror film." It remains to be seen whether he'll follow through with any of them.
Career Resurrection: Tarantino has a knack for bringing forgotten or underappreciated film genres back to attention. Certain actors whose career has been in a slump for a while have had their careers resurrected by appearing in his movies. The most spectacular example is John Travolta, who was a has-been ever since the Saturday Night Fever craze died down, but became an A-list star again after starring in Pulp Fiction. Other actors Tarantino brought back in the limelight haven't had quite the same level of career revival but still became more notable in mainstream media again include Pam Grier, Robert Forster, Harvey Keitel and Kurt Russell. Additionally, Jennifer Jason Leigh's performance in The Hateful 8 earned her her first ever Academy Award nomination, following years in which she had been acting in somewhat more low-key projects.
Playing Against Type: Arguably Jackie Brown. Honestly, anyone used to viewing Quentin as a "gore-freak" making uber-"wild-and-crazy" flicks are in for a shock upon seeing this (relatively) slow-paced and mellow character-oriented piece. Additionally, it's the one straight adaptation of his filmography, basing itself off of the Elmore Leonard novel Rum Punch.
Sally Menke edited all of his movies up through Inglourious Basterds until her tragic death in 2010. His subsequent films have been edited by Fred Raskin.
The cinematography for all of his films since Kill Bill have been done by Robert Richardson, with the exception of Death Proof (which Quentin Tarantino did himself). Before this, Andrzej Sekula shot both Reservoir Dogs and Pulp Fiction in addition to Tarantino's segment of Four Rooms.
Along with aforementioned projects he's announced and never followed through with, Tarantino was also the first choice to direct both Speed and Men in Black, but he turned both films down in order to create Pulp Fiction.
He famously lobbied to direct Casino Royale...since the 1990s. No less a person than Sean Connery said it would be an inspired idea.
Early in his career, Quentin tossed around the idea of making a superhero film about Luke Cage.