Memento has many elements which fascinate me.

Memory is an obvious theme throughout the movie. What is interesting is that there are two intertwined sets of scenes which converge at the end of the movie. The first is in color and goes backwards. These scenes are presented to the audience much in the way Leonard sees them -- we have no knowledge (recollection for Leonard) of events which preceded them, so we interpret things as we see fit. The second set of scenes is in black & white and proceeds in a linear (forward) fashion, yet mostly deals with a secondary story of Sammy and his wife. These scenes present a traditional storytelling view as we await what happens between the cuts of these scenes, trying to anticipate what happens based on past history.

Another theme is reality/truth. Leonard takes polariods and has tattoos to remind him of facts -- people, places, and events. In one point of the movie, Teddy tells Leonard that these things are meaningless for Leonard since he can't verify these things without memory. Leonard mentions to Teddy that photographs are real -- memories can fade with time or can change, but things such as photographs resist these factors. (Forgive me, I'm paraphrasing here from my own unreliable memory of the movie) However, we see at the end that the polaroids and comments written on those snapshots serve only to reinforce a warped view of reality. Towards the ending, through Leonard's monologue while in the car(s), we see that facts can be bent to provide different 'truths', and, in short, we do define our own realities and memories. In fact, only Teddy, who Leonard dubbed as a liar, is aware of the real truth.

Lastly, one of the many aspects of the film I enjoyed was the twists and turns of the story. In the beginning of the movie, we are led to believe that Teddy is scum while Natalie and Leonard are victims. Because of circumstances we learn later, it is Teddy who I feel somewhat sorry for; he is the only one who seems to care about Leonard, even though he is a crooked cop who uses Leonard. Natalie is manipulative with various 'faults' of her own and not the caring, sweet, poor victim we once thought her to be. Leonard, too, is not the vengeful widower initially portrayed, but he is very warped. His own condition does not allow him to savor a sense of justice. It may even be argued that he doesn't want to believe that he can attain a sense of closure. He cannot live in the present, and he cannot accept that his wife left him and that he cannot live a functional life. Instead, this mission of searching for John G. is the only way in which he can continue living. Hence, whenever he tracks down John G. and achieves relief at that moment, we are led to assume that he will only destroy those polaroids and never tattoo his left chest. Searching for John G. is the only purpose he has left in life, a purpose which, through deceiving himself, he will keep alive.

There are many other intriguing (at least, for me) aspects of the movie -- Doesn't the name "Lenny" remind you of the character (and his 'condition') in Of Mice and Men? I think I may go see it a second time to see if I can understand this great movie better.