Movietally is an online service currently in beta, which allows you to catalogue and rate the movies you've seen and get recommendations for movies that you might like to see.

When searching for a movie in Movietally, you're shown related tags for that movie. You can click through the tags that are of interest to you to locate other movies with the same tags. Each movie in the database also has a link out to other movie recommendations from users that have seen the movie in question, as well as reviews. Movietally is still in its infancy, and there are not a lot of movies listed. So sign up and help build this cool little movie catalogue collection.

[Via eHub]