I'm surprised no-one's mentioned a site called Letterboxd on this board.

To explain a bit: Letterboxd is a hybrid movie database/social network that you can use keep track of all the movies you've seen, share your viewing history and favourite films, make lists, and write reviews/score movies. (Think like MAL, but for movies/films in general.)

I spent the better part of a night tweaking my profile, remembering and adding all the movies I've seen, setting favorites and cobbling together some lists - and I found it rather fun. (YMMV, of course.)

If this sounds at all interesting to you, give it a shot