The Bourne Ultimatum had lots of memorable scenes. My two favorites actually both feature Julia Stiles as Nicky Parsons as well as Matt Damon as Jason Bourne.
The first has Nicky explaining to Jason why she helps him - tying up one of those loose ends from the first movie, which I didn't quite realize was a loose end until this scene (up until which, I thought Nicky was just attracted to Jason).
And the other is the extraordinary fight scene between Jason and Desh (played by Joey Ansah). This scene - with Nicky getting a little involved in the fight - is in a league with the classic Sean Connery - Robert Blake fight in From Russia With Love.
But with all of these superb ingredients, I'm still wondering why these movies are so good, so enjoyable - given that the essential elements of the Bourne series plot are so familiar. We've seen many movies about spies and secret agents abused by their employers. Many movies about secret agent amnesia. Many movies about spies on the run for their lives, helped by beautiful women, civilian or agent - some of whom survive, some not.
What makes the Bourne series different?
If I told you, my life would be forfeit...
No, only kidding - the truth is I don't completely know.
But here's my best guess at the moment: it's because the action - again, especially in the first and third movies - is almost truly non-stop. No time out is taken for James Bondian humor (which works well for James) and even the flirting is minimal (again, much less than with James Bond, which also works well for him).
These Bourne movies may even be a distinct genre - minimalist action movies ... and I have a feeling they'll even play better in retrospect.
This is just a piece of the fight scene.