Now coming to "Memento" - the movie was presented in a unique style - that was also quite fine - but leaves you feeling a wee bit disconnected - you are not sure that the conclusion is right and I don't like that.
And Nolan's recent "Inception" - there was no need for that kind of ending. I don't want to add spoilers here - but you will know what I mean if you have seen the movie.
Last but not the least, while I can easily forgive Memento and Inception - simply because of the brilliant concepts they present I cannot say the same of "Duplicity" . In the end the one who is duped is the viewer. It seemed to be a case of the director trying to be too clever - and Julia Roberts (for all her so-called charm) irritated me to the core as did Clive Owen who seemed to think his role in there was to just look smug. A pity that for he was quite good in "Inside Man".