I just saw Science of Sleep last night. This is my kind of film: quirky and unique.
I don't think I'd call it the best film of the year, though, because of the ending. I just didn't understand why Stephan kept spouting all of these hurtful things to Stephanie. It struck me as really out of character...not at all like his dreamworld persona.
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Overall though, an excellent film! Beautiful and very inventive. Bravo, Senor Gondry!
PS- My pick for best of the year (with the caveat that I certainly haven't seen all the films I wanted to this year) would probably be The Prestige. Although, come to think of it, I was let down by the end of that film as well...