I've seen and like most of his films. For anyone getting fresh into Lars' movies, i can recommend Melancholia (2011).
Kirsten Dunst Charlotte Gainsbourg Kiefer Sutherland Udo Kier John Hurt Charlotte Rampling ...
The underlying sci-fi element of the movie is well executed and it wraps his usual soul- and heart-breaking screenplay in a way, that doesn't leave you staring at the emotional void and bleak sadness his movies usually leave behind.