The Dream Life of Angels: not so much without dialogue, but without soundtrack.
Celebration (Festen): It’s once of the Dogme 93 movies, but it’s still left an impression on me that I will never forget. No soundtrack on this one either.
Poster Boy: I was REALLY impressed by this movie, mostly because for once I forgot the quality of the filming over the very compelling storyline. That’s when you know low-fi can have legs.