I love Charlotte Gainsbourg. Partly it's because of her movies — but mostly it's her underbite.
Gainsbourg discusses her acting and singing careers in an interview with AnOther magazine, and she's impressive in both spheres. I especially liked her in My Wife Is An Actress and Love, Etc. — maybe slightly less so in The Science of Sleep, but only because her character was written as too much of a Manic Pixie Dream Girl. She tends to project a mysterious quality and a sense that even her characters don't fully understand their own motivations — a sense borne out, perhaps, by her statement that, "What I do and the decisions I make – whether to make music or be in a film – are very instinctive and I only understand much later, in retrospect, my reasons for doing things." But: the underbite.