Letterboxd - Letterboxd is a social site for sharing your taste in film, now in public beta.
IMDb - Internet Movie Database
TMDB - free movie database
TasteDive - TasteDive recommends similar music (musicians, bands), movies, TV shows, books, authors and games, based on what you like.
MovieLens - MovieLens helps you find non-commercial, personalized movie recommendations.
Simkl - Simkl is a TV, anime, and movie tracker that keeps a history of all the shows and movies you watch in one, central location. It’s a mobile app, a website, Google Chrome extension to keep track of everything you watch and integrates with many TV apps